Intermediate film for laminated glass, and laminated glass

ABSTRACT

Provided is an interlayer film for laminated glass capable of effectively enhancing the sound insulating property at 6300 Hz while effectively preventing deterioration in sound insulating property at 3150 Hz in laminated glass. An interlayer film for laminated glass according to the present invention has a one-layer structure or a two or more-layer structure and includes a resin layer containing a resin and a plasticizer. The interlayer film has a resonance frequency X of 550 Hz or more and 740 Hz or less, a loss factor Y in a secondary mode of 0.35 or more, and satisfies a formula: Y&gt;0.0008X−0.142 in a measurement of resonance frequency in a secondary mode in a damping test for laminated glass according to a central exciting method of laminated glass, when the laminated glass is obtained by arranging the interlayer film between two glass plates of 25 mm wide, 300 mm long and 2 mm thick.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation application of patent applicationSer. No. 16/613,071, filed on Nov. 12, 2019, which is a 371 applicationof Application Serial No. PCT/JP2018/019314, filed on May 18, 2018,which is based on Japanese Patent Application Nos. 2017-099867,2017-143120 and 2018-017726 filed on May 19, 2017, Jul. 24, 2017 andFeb. 2, 2018, respectively, the entire contents of which are herebyincorporated by reference.

TECHNICAL FIELD

The present invention relates to an interlayer film for laminated glasswhich is used for obtaining laminated glass. Moreover, the presentinvention relates to laminated glass prepared with the interlayer filmfor laminated glass.

BACKGROUND ART

Since laminated glass generally generates only a small amount ofscattering glass fragments even when subjected to external impact andbroken, laminated glass is excellent in safety. As such, the laminatedglass is widely used for automobiles, railway vehicles, aircraft, ships,buildings and the like. The laminated glass is produced by sandwichingan interlayer film for laminated glass between a pair of glass plates.

Examples of the interlayer film for laminated glass include asingle-layered interlayer film having a one-layer structure and amulti-layered interlayer film having a two or more-layer structure.

The following Patent Document 1 discloses a laminate (interlayer film)in which a sound insulating layer is located between at least twoadhesive layers. Laminated glass that is prepared by pressure bonding bysandwiching the laminate between glass plates having a thickness of 2mm, and retaining under the condition at a temperature of 140° C. and apressure of 1 MPa for 60 minutes has the following performance. The lossfactor α at 20° C., 2000 Hz measured by a damping test according to acentral exciting method of the laminated glass is 0.2 or more. Regardingthe laminated glass after retaining the laminated glass at 18° C. for 1month, the ratio β/α of the loss factor β at 20° C., 2000 Hz measured bya damping test according to a central exciting method, to the lossfactor α is 0.70 or more. The sound insulating layer may contain anelastomer. The sound insulating layer does not contain a plasticizer.

Also, the following Patent Document 2 discloses an interlayer film inwhich a layer containing polyvinyl acetal and a layer containingpolyolefin are layered.

Also, the following Patent Document 3 discloses an intermediate layer(interlayer film) arranged between two glass plates. In the interlayerfilm for laminated glass having the intermediate layer, the resonancefrequency f₂ of the second resonance mode determined by measurement ofmechanical impedance at 20° C. (HIM) is between 760 Hz and 1000 Hz. Theloss factor 02 of the second resonance mode determined by MIM in thesame condition is 0.25 or more.

RELATED ART DOCUMENT Patent Document

-   Patent Document 1: JP 2016-108225 A-   Patent Document 2: WO 2011/016494 A1-   Patent Document 3: Jr 2015-525185 T

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

As described in Patent Documents 1, 2, an interlayer film having a layerprepared with a thermoplastic component other than a polyvinyl acetalresin is known. However, in laminated glass using this interlayer film,the sound insulating property cannot be sufficiently high.

In recent years, needs for improvement of sound insulating property arediversified in automobile fields. When the glass plate is thinned forreducing the weight, the coincidence frequency shifts to the highfrequency side, so that the sound insulating property in the highfrequency region deteriorates. Therefore, it is conceived that use of asound insulating interlayer film having a high Young's modulus preventsthe coincidence frequency from shifting to the high frequency side. Inluxury cars, thick glass plates are used to emphasize the silence in thevehicle interior. However, when a sound insulating interlayer filmhaving a high Young's modulus is used, the sound insulating propertytends to deteriorate in the medium frequency region due to the shift ofthe coincidence frequency on the low frequency side. If one caneffectively enhance the sound insulating property at 6300 Hz whileeffectively preventing deterioration in the sound insulating property at3150 Hz, it will be possible to improve the silence in the vehicleinterior. Conventional laminated glass prepared with a relatively thickglass plate has a problem that it is difficult to effectively enhancethe sound insulating property at 6300 Hz while effectively preventingdeterioration in sound insulating property at 3150 Hz.

It is an object of the present invention to provide an interlayer filmfor laminated glass capable of effectively enhancing the soundinsulating property at 6300 Hz while effectively preventingdeterioration in sound insulating property at 3150 Hz in laminatedglass. Moreover, the present invention also aims at providing laminatedglass prepared with the interlayer film for laminated glass.

For Solving the Problems

According to a broad aspect of the present invention, there is providedan interlayer film for laminated glass (hereinafter, also described asinterlayer film) having a one-layer structure or a two or more-layerstructure, the interlayer film including a resin layer containing aresin and a plasticizer, and the interlayer film having a resonancefrequency X of 550 Hz or more and 740 Hz or less, a loss factor Y in asecondary mode of 0.35 or more, and satisfying a formula:Y>0.0008X−0.142 in a measurement of resonance frequency in a secondarymode in a damping test for laminated glass according to a centralexciting method of laminated glass, when the laminated glass is obtainedby arranging the interlayer film between two glass plates of 25 mm wide,300 mm long and 2 mm thick.

In a specific aspect of the interlayer film according to the presentinvention, the resin layer contains a thermoplastic resin, or contains acured product of a photocurable compound or a moisture-curable compound.

In a specific aspect of the interlayer film according to the presentinvention, the resin layer contains a thermoplastic resin.

In a specific aspect of the interlayer film according to the presentinvention, the thermoplastic resin is a thermoplastic elastomer.

In a specific aspect of the interlayer film according to the presentinvention, the thermoplastic elastomer is an aliphatic polyolefin.

In a specific aspect of the interlayer film according to the presentinvention, the aliphatic polyolefin is a saturated aliphatic polyolefin.

In a specific aspect of the interlayer film according to the presentinvention, the plasticizer is a plasticizer other than an organic esterplasticizer.

In a specific aspect of the interlayer film according to the presentinvention, the plasticizer is paraffin oil.

In a specific aspect of the interlayer film according to the presentinvention, the interlayer film includes a first layer, and a secondlayer arranged on a first surface side of the first layer.

In a specific aspect of the interlayer film according to the presentinvention, when the overall thickness of the interlayer film forlaminated glass is T, the thickness of the first layer is 0.25T or less.

In a specific aspect of the interlayer film according to the presentinvention, the interlayer film includes a third layer arranged on asecond surface side opposite to the first surface side of the firstlayer.

In a specific aspect of the interlayer film according to the presentinvention, the second layer contains a thermoplastic resin and aplasticizer, and the third layer contains a thermoplastic resin and aplasticizer.

In a specific aspect of the interlayer film according to the presentinvention, the interlayer film is used for obtaining laminated glass bybeing arranged between a first glass plate having a thickness of 1.8 mmor more and 3 mm or less, and a second glass plate.

In a specific aspect of the interlayer film according to the presentinvention, the interlayer film is used for obtaining laminated glass bybeing arranged between a first glass plate and a second glass plate, anda total of a thickness of the first glass plate and a thickness of thesecond glass plate is 3.6 mm or more and 6 mm or less.

In a broad aspect of the present invention, there is provided alaminated glass including a first lamination glass member, a secondlamination glass member and the interlayer film for laminated glassdescribed above, the interlayer film for laminated glass being arrangedbetween the first lamination glass member and the second laminationglass member.

Effect of the Invention

The interlayer film for laminated glass according to the presentinvention has a one-layer structure or a two or more-layer structure.The interlayer film for laminated glass according to the presentinvention includes a resin layer containing a resin and a plasticizer.The interlayer film for laminated glass according to the presentinvention is arranged between two glass plates of 25 mm wide, 300 mmlong and 2 mm thick, to obtain laminated glass, and a resonancefrequency in a secondary mode of the laminated glass according to acentral exciting method is measured by a damping test of laminatedglass. In this measurement, in the interlayer film for laminated glassaccording to the present invention, the resonance frequency X is 550 Hzor more and 740 Hz or less, the loss factor Y in the secondary mode is0.35 or more, and a formula: Y>0.0008X−0.142 is satisfied. Since theinterlayer film for laminated glass according to the present inventionhas the configuration as described above, it is possible to effectivelyenhance the sound insulating property at 6300 Hz while effectivelypreventing deterioration in sound insulating property at 3150 Hz inlaminated glass prepared with the interlayer film for laminated glassaccording to the present invention.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional view schematically showing an interlayer film forlaminated glass in accordance with a first embodiment of the presentinvention.

FIG. 2 is a sectional view schematically showing an interlayer film forlaminated glass in accordance with a second embodiment of the presentinvention.

FIG. 3 is a sectional view schematically showing an example of laminatedglass prepared with the interlayer film for laminated glass shown inFIG. 1.

FIG. 4 is a sectional view schematically showing an example of laminatedglass prepared with the interlayer film for laminated glass shown inFIG. 2.

FIG. 5 is a chart showing one example of the relationship between thefrequency and the transmission loss of the laminated glass.

MODE(S) FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.

(Interlayer Film for Laminated Glass)

The interlayer film for laminated glass according to the presentinvention (hereinafter, sometimes described as interlayer film) has aone-layer structure or a two or more-layer structure.

The interlayer film according to the present invention includes a resinlayer containing a resin and a plasticizer. It is preferred that theinterlayer film according to the present invention include a resin layercontaining a resin other than a polyvinyl acetal resin.

The interlayer film according to the present invention is arrangedbetween two glass plates of 25 mm wide, 300 mm long and 2 mm thick, toobtain laminated glass, and a resonance frequency in a secondary mode ofthe laminated glass according to a central exciting method is measuredby a damping test of laminated glass. In the interlayer film forlaminated glass according to the present invention, in this measurement,the resonance frequency X is 550 Hz or more and 740 Hz or less, the lossfactor Y in the secondary mode is 0.35 or more, and the followingformula (1) is satisfied.

Y>0.0008X−0.142  (1)

Since the interlayer film according to the present invention has theconfiguration as described above, it is possible to effectively enhancethe sound insulating property at 6300 Hz while effectively preventingdeterioration in sound insulating property at 3150 Hz in laminated glassprepared with the interlayer film according to the present invention.

FIG. 5 is a chart showing one example of the relationship between thefrequency and the transmission loss of the laminated glass. In theinterlayer film according to the present invention, it is possible toeffectively enhance the sound insulating property at 6300 Hz around B inFIG. 5 while effectively preventing deterioration in sound insulatingproperty around A in FIG. 5.

In luxury cars, thick glass plates are used to emphasize the silence inthe vehicle interior. In the present invention, it is possible toeffectively enhance the sound insulating property even when a thickglass plate having a thickness of 1.8 mm or more is used. Further, inthe present invention, it is possible to effectively enhance the soundinsulating property even when a thick glass plate having a thickness of2 mm or more is used.

The glass plates used in measurement of the resonance frequency and theloss factor are two plates of clear glass in conformity with JISR3202:1996.

The resonance frequency and the loss factor can be specifically measuredin the following manner.

The interlayer film is cut into a size of 25 mm wide and 300 mm long. Asthe first lamination glass member, and the second lamination glassmember, two glass plates (clear float glass, 25 mm wide, 300 mm long and2 mm thick) are prepared. The interlayer film is sandwiched between thetwo glass plates to obtain a laminate. The laminate is put into a rubberbag and the inside thereof is degassed for 20 minutes at a degree ofvacuum of 2.6 kPa, after which the laminate is transferred into an ovenwhile keeping the laminate degassed, and furthermore, held in place at90° C. for 30 minutes and pressed under vacuum to subject the laminateto preliminary press-bonding. The preliminarily press-bonded laminate issubjected to press-bonding for 20 minutes under conditions of 135° C.and a pressure of 1.2 MPa in an autoclave to obtain a sheet of laminatedglass. The obtained laminated glass is stored in an environment at roomtemperature of 23±2° C. and a humidity of 25±5%. After 8 weeks aftercompletion of the autoclave, the obtained laminated glass is excitedwith a vibration generator for damping test (“Vibrator G21-005D”available from Shinken. Co., Ltd.) in a thermostatic oven at 20° C. Theresultant vibration characteristic is amplified with a mechanicalimpedance measuring device (“XG-81” available from RION Co., Ltd.), andthe vibration spectrum is analyzed with a FFT spectrum analyzer (“FFTanalyzer HP3582A” available from Yokogawa Hewlett Packard) to measure aresonance frequency and the loss factor.

From the viewpoint of exerting the effect of the present inventionfurther effectively, the resonance frequency X is preferably 580 Hz ormore, more preferably 600 Hz or more, and is preferably 720 Hz or less,more preferably 680 Hz or less.

From the viewpoint of exerting the effect of the present inventionfurther effectively, the loss factor Y is preferably 0.40 or more, morepreferably 0.45 or more, and is preferably 0.70 or less, more preferably0.60 or less.

From the viewpoint of further enhancing the sound insulating property,it is preferred that the glass transition temperature of the resin layerlie within a temperature range of −10° C. to 10° C. When the glasstransition temperature of the resin layer lies within a temperaturerange of −10° C. to 10° C., the resonance frequency X and the lossfactor Y are easy to satisfy the above ranges, and easily satisfy theabove formula (1).

From the viewpoint of still further enhancing the sound insulatingproperty, it is preferred that the glass transition temperature of theresin layer lies within a temperature range of −8° C. to 0° C.

As a method for measuring the glass transition temperature, a method ofmeasuring viscoelasticity by using “ARES-G2” available from TAInstruments directly after keeping the obtained interlayer film for 12hours in an environment of room temperature of 23±2° C. and a humidityof 25±5% can be recited. It is preferred to use a parallel plate with adiameter of 8 mm as a jig, and measure the glass transition temperatureunder the condition in which the temperature is decreased from 100° C.to −50° C. at a temperature decreasing rate of 3° C./minute and underthe condition of a frequency of 1 Hz and a strain of 1%. For aninterlayer film having a two or more-layer structure, the layers may bedelaminated, and the glass transition temperature of the layer to bemeasured may be measured.

The interlayer film according to the present invention may have aone-layer structure and may have a two or more-layer structure. Theinterlayer film according to the present invention may have a two-layerstructure, may have a three-layer structure, and may have a three ormore-layer structure.

The interlayer film according to the present invention may have aone-layer structure of only a first layer. In this case, the first layeris the resin layer.

From the viewpoint of effectively enhancing the sound insulatingproperty and adhesiveness between layers, the interlayer film accordingto the present invention may include a first layer, and a second layerarranged on a first surface side of the first layer. In this case, it ispreferred that the first layer be the resin layer.

From the viewpoint of effectively enhancing the sound insulatingproperty and adhesiveness between layers, the interlayer film accordingto the present invention may include a first layer, a second layerarranged on a first surface side of the first layer, and a third layerarranged on a second surface side opposite to the first surface side ofthe first layer. In this case, it is preferred that the first layer bethe resin layer.

From the viewpoint of effectively enhancing the sound insulatingproperty and adhesiveness between the interlayer film and the glassplates, it is preferred that the resin layer be not a surface layer inthe interlayer film, and it is preferred that the resin layer be anintermediate layer in the interlayer film. It is to be noted that theresin layer may be a surface layer in the interlayer film.

From the viewpoint of enhancing the transparency of the laminated glass,the visible light transmittance of the interlayer film is preferably 70%or more, more preferably 80% or more, further preferably 85% or more.

The visible light transmittance is measured at a wavelength ranging from380 to 780 nm by using a spectrophotometer (“U-4100” available fromHitachi High-Tech Science Corporation) in conformity with JISR3211:1998.

The visible light transmittance of the interlayer film may be measuredwhile the interlayer film is arranged between two sheets of clear glass.

For enhancing the visible light transmittance, the interlayer film andthe resin layer may not contain a coloring agent, or may not containcarbon black.

The interlayer film is arranged between a first glass plate and a secondglass plate to suitably obtain laminated glass. The total of thethickness of the first glass plate and the thickness of the second glassplate is preferably 3.6 mm or more, more preferably 4 mm or more,further preferably 4.2 mm or more. In this case, it is possible toimprove the silence in the vehicle interior, and it is possible toeffectively enhance the sound insulating property of the laminated glassby the configuration of the present invention. The total of thethickness of the first glass plate and the thickness of the second glassplate is preferably 6 mm or less, more preferably 5 mm or less, furtherpreferably 4.6 mm or less. In this case, it is possible to reduce theweight of the laminated glass.

The interlayer film is arranged between a first glass plate and a secondglass plate to suitably obtain laminated glass. The interlayer film ispreferably used for obtaining laminated glass by being arranged betweena first glass plate having a thickness of 1.8 mm or more (preferably 2mm or more, more preferably 2.1 mm or more), and a second glass plate.In this case, it is possible to improve the silence in the vehicleinterior, and it is possible to effectively enhance the sound insulatingproperty of the laminated glass by the configuration of the presentinvention. The interlayer film is preferably used for obtaininglaminated glass by being arranged between a first glass plate having athickness of 3 mm or less (preferably 2.6 mm or less, more preferably2.3 mm or less), and a second glass plate. In this case, it is possibleto reduce the weight of the laminated glass.

Hereinafter, specific embodiments of the present invention will bedescribed with reference to the drawings.

FIG. 1 is a sectional view schematically showing an interlayer film forlaminated glass in accordance with a first embodiment of the presentinvention.

An interlayer film 11 shown in FIG. 1 is a multi-layered interlayer filmhaving a two or more-layer structure. The interlayer film 11 is used forobtaining laminated glass. The interlayer film 11 is an interlayer filmfor laminated glass. The interlayer film 11 includes a first layer 1, asecond layer 2 and a third layer 3. The second layer 2 is arranged on afirst surface side 1 a of the first layer 1 to be layered thereon. Thethird layer 3 is arranged on a second surface 1 b side at the oppositeside of the first surface 1 a of the first layer 1 to be layeredthereon. The first layer 1 is an intermediate layer. Each of the secondlayer 2 and the third layer 3 is a protective layer and is a surfacelayer in the present embodiment. The first layer 1 is arranged betweenthe second layer 2 and the third layer 3 to be sandwiched therebetween.Accordingly, the interlayer film 11 has a multilayer structure (secondlayer 2/first layer 1/third layer 3) in which the second layer 2, thefirst layer 1, and the third layer 3 are layered in this order.

In the interlayer film 11, it is preferred that the first layer 1 be theresin layer. The second layer 2 may be the resin layer, or the thirdlayer 3 may be the resin layer.

In this connection, other layers may be arranged between the secondlayer 2 and the first layer 1 and between the first layer 1 and thethird layer 3, respectively. It is preferred that the second layer 2 andthe first layer 1, and the first layer 1 and the third layer 3 bedirectly layered. Examples of another layer include an adhesive layer,and a layer containing polyethylene terephthalate and the like.

FIG. 2 is a sectional view schematically showing an interlayer film forlaminated glass in accordance with a second embodiment of the presentinvention.

An interlayer film 11A shown in FIG. 2 is a single-layered interlayerfilm having a one-layer structure. The interlayer film 11A is a firstlayer. The interlayer film 11A is used for obtaining laminated glass.The interlayer film 11A is an interlayer film for laminated glass.

In the interlayer film 11A, the interlayer film 11A per se is the resinlayer.

Hereinafter, the details of the resin layer (which may be a firstlayer), the first layer, the second layer, and the third layerconstituting the interlayer film according to the present invention, andthe details of each ingredient contained in the resin layer (which maybe a first layer), the first layer, the second layer, and the thirdlayer will be described.

(Resin in First Layer)

Examples of the resin include thermosetting resins and thermoplasticresins. The resin may be a cured product of a photocurable compound or amoisture-curable compound. The cured product of a photocurable compoundor a moisture-curable compound may be used as a thermoplastic resin.

It is preferred that the first layer (the resin layer) contain athermoplastic resin (hereinafter, sometimes described as a thermoplasticresin (1)), or contain a cured product of a photocurable compound or amoisture-curable compound (hereinafter, sometimes described as a curedproduct (1)). The thermoplastic resin (1) and the cured product (1) arecollectively called a resin (1). One kind of the resin (1) may be usedalone, and two or more kinds thereof may be used in combination.

From the viewpoint of effectively enhancing the sound insulatingproperty, it is preferred that each of the thermoplastic resins in thethermoplastic resin layer and the first layer be a thermoplasticelastomer. The thermoplastic resin means a resin that softens andexhibits plasticity when it is heated, and hardens when it is cooled toroom temperature. Among the thermoplastic resins, especially thethermoplastic elastomer means a resin that softens and exhibitsplasticity when it is heated, and hardens to exhibits rubber elasticitywhen it is cooled to room temperature (25° C.)

In 100% by weight of the thermoplastic resin in the thermoplastic resinlayer or the first layer, the content of the thermoplastic elastomer ispreferably 50% by weight or more, more preferably 60% by weight or more,further preferably 70% by weight or more, especially preferably 80% byweight or more, most preferably 90% by weight or more. The whole ofthermoplastic resin in the thermoplastic elastomer layer may be thethermoplastic elastomer.

The present inventors investigated for enhancing of the sound insulatingproperty of laminated glass in an interlayer film including a layerprepared with a resin. As a result, the present inventors found aconfiguration with which the sound insulating property of laminatedglass can be enhanced. As a result, the present inventors found aconfiguration capable of effectively enhancing the sound insulatingproperty at 6300 Hz while effectively preventing deterioration in soundinsulating property at 3150 Hz, in laminated glass including aninterlayer film having a layer prepared with a resin component(thermoplastic component or the like) other than a polyvinyl acetalresin.

The present inventors investigated for enhancing the sound insulatingproperty of laminated glass also in an interlayer film including a layerprepared with a thermoplastic component other than a polyvinyl acetalresin. As a result, the present inventors found a configuration capableof effectively enhancing the sound insulating property at 6300 Hz whileeffectively preventing deterioration in sound insulating property at3150 Hz, also in laminated glass including an interlayer film having alayer prepared with a resin component (thermoplastic component or thelike) other than a polyvinyl acetal resin.

Examples of the thermoplastic resin (1) include an aliphatic polyolefin,polystyrene, an ethylene-vinyl acetate copolymer resin, anethylene-acrylic acid copolymer resin, a polyurethane resin, a polyvinylalcohol resin, a polyvinyl acetate resin, and a polyester resin, and thelike.

The thermoplastic resins exemplified above can be a thermoplasticelastomer by adjusting the molecular structure, the polymerizationdegree and the like of the resin.

From the viewpoint of effectively enhancing the sound insulatingproperty, it is preferred that the resin (1) in the resin layer be athermoplastic resin. The resin layer may be a thermoplastic resin layer.From the viewpoint of effectively enhancing the sound insulatingproperty, the thermoplastic resin be more preferably a polyvinyl acetalresin, a polyester resin, or polyvinyl acetate, further preferably apolyester resin or polyvinyl acetate, especially preferably polyvinylacetate.

The photocurable compound or the moisture-curable compound is preferablya curable compound having a (meth)acryloyl group, and is more preferablya (meth)acryl polymer. The resin is preferably a curable compound havinga (meth)acryloyl group, and is more preferably a (meth)acryl polymer.

It is preferred that the (meth)acryl polymer be a polymer of apolymerizable composition containing a curable compound having a(meth)acryloyl group. The polymerizable composition contains apolymerizable component. In order to effectively form the cured productin the layer containing the cured product, the polymerizable compositionmay contain a photoreaction initiator. The polymerizable composition maycontain an auxiliary for accelerating the curing reaction together withthe photoreaction initiator. Representatives of the curable compoundhaving a (meth)acryloyl group include (meth)acrylic ester. It ispreferred that the (meth)acrylic polymer be a poly(meth)acrylic ester.

For effectively obtaining the effect of the present invention, it ispreferred that the polymerizable component include a (meth)acrylic esterhaving a cyclic ether structure, a (meth)acrylic ester having anaromatic ring, a (meth)acrylic ester having a polar group, or an acyclic(meth)acrylic ester having 6 or less carbon atoms in the side chain. Byusing such a preferred (meth)acrylic ester, it is possible to enhanceboth the sound insulating property and the ability to prevent foaming ingood balance.

Examples of the (meth)acrylic ester having a cyclic ether structureinclude glycidyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate glycidylether, 3-hydroxypropyl (meth)acrylate glycidyl ether, 4-hydroxybutylacrylate glycidyl ether, 5-hydroxypentyl (meth)acrylate glycidyl,6-hydroxyhexyl (meth)acrylate glycidyl ether;(3-methyloxetane-3-yl)methyl (meth)acrylate,(3-propyloxetane-3-yl)methyl (meth)acrylate, (3-ethyloxetane-3-yl)methyl(meth)acrylate, (3-butyloxetane-3-yl)methyl (meth)acrylate,(3-ethyloxetane-3-yl)ethyl (meth)acrylate, (3-ethyloxetane-3-yl)propyl(meth)acrylate, (3-ethyloxetane-3-yl)butyl (meth)acrylate,(3-ethyloxetane-3-yl)pentyl (meth)acrylate, (3-ethyloxetane-3-yl)hexyl(meth)acrylate; tetrahydrofurfuryl (meth)acrylate, γ-butyrolactone(meth)acrylate, (2,2-dimethyl-1,3-dioxolanedioxolane-4-yl)methyl(meth)acrylate, (2-methyl-2-ethyl-1,3-dioxolane-4-yl)methyl(meth)acrylate, (2-methyl-2-isobutyl-1,3-dioxolane-4-yl)methyl(meth)acrylate, (2-cyclohexyl-1,3-dioxolane-4-yl)methyl (meth)acrylate,tetrahydrofurfuryl alcohol acrylic acid multimer ester;tetrahydro-2H-pyran-2-yl-(meth)acrylate,2-{1-[(tetrahydro-2H-pyran-2-yl)oxy]-2-methylpropyl}(meth)acrylate,cyclic trimethylol propane formal acrylate, (meth)acryloyl morpholineand the like. From the viewpoint of effectively obtaining the effect ofthe present invention, it is especially preferred that the (meth)acrylicester having a cyclic ether structure be tetrahydrofurfuryl(meth)acrylate, or cyclic trimethylol propane formal acrylate.

Examples of the (meth)acrylic ester having an aromatic ring includebenzyl acrylate, phenoxypolyethyleneglycol acrylate and the like.

Examples of the (meth)acrylic ester having a polar group include(meth)acrylic esters having a hydroxyl group, an amide group, an aminogroup, and an isocyanate group or the like as the polar group.

Examples of the (meth)acrylic ester having a hydroxyl group include2-hydroxyethyl (meth)acrylate, and hydroxypropyl (meth)acrylate and thelike.

Examples of the (meth)acrylic ester having an amide group includeN,N-dimethylaminopropyl (meth)acrylamide, N,N-dimethyl (meth)acrylamide,(meth)acryloyl morpholine, N-isopropyl (meth)acrylamide, andN-hydroxyethyl (meth)acrylamide and the like.

Examples of the (meth)acrylic ester having an amide group or an aminogroup include N-dialkylaminoalkyl (meth)acrylamide, andN,N-dialkylaminoalkyl (meth)acrylamide and the like.

Examples of the (meth)acrylic ester having an isocyanate group includetriallylisocyanurate, and derivatives thereof and the like.

The above-described (meth)acrylic ester may be a polycarboxylic esterhaving a (meth)acryloyl group. Examples of the polycarboxylic esterhaving a (meth)acryloyl group include 2-acryloyloxyethyl succinate andthe like.

From the viewpoint of effectively obtaining the effect of the presentinvention, it is preferred that the polymerizable component be a(meth)acrylic ester having a hydroxyl group, especially preferably2-hydroxyethyl (meth)acrylate, or hydroxypropyl (meth)acrylate.

Examples of the acyclic (meth)acrylic ester having 6 or less carbonatoms in the side chain include methyl (meth)acrylate, ethyl(meth)acrylate, propyl (meth)acrylate, and butyl (meth)acrylate and thelike.

For effectively obtaining the effect of the present invention, it ispreferred that the blending amount of the acyclic (meth)acrylic esterhaving 8 or more carbon atoms in the side chain in 100% weight of thepolymerizabie component be less than 20% by weight.

Examples of the (meth)acrylic ester include besides the compounds asrecited above, diethyleneglycol monoethylether (meth)acrylate, isobornyl(meth)acrylate, 3-methoxybutyl (meth)acrylate,2-acryloyloxyethyl-2-hydroxypropylphthalate,2-acryloyloxyethyl-2-hydroxylpropylphthalate, cyclohexyl (meth)acrylate;ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate,tetraethylene glycol di(meth)acrylate, 1,6-hexane diol di(meth)acrylate,1,9-nonane diol di(meth)acrylate, polytetramethylene glycoldi(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-butylene glycoldi(meth)acrylate, 2,2-bis[4-(acryloxyethoxy)phenyl]propanedi(meth)acrylate; trimethylolpropane tri(meth)acrylate, pentaerythritoltri(meth)acrylate, pentaerythritol tetra(meth)acrylate,dipentaerythritol penta(meth)acrylate, dipentaerythritolhexa(meth)acrylate, tri(2-acryloyloxyethyl)phosphate, tetramethylolmethane tri(meth)acrylate, tetramethylol propane tetra(meth)acrylate,derivatives thereof and the like.

One kind of the (meth)acrylic ester may be used alone, and two or morekinds thereof may be used in combination.

The above-described (meth)acryl polymer may be a homopolymer of theabove-described (meth)acrylic ester, or may be a copolymer of apolymerizable component containing the above-described (meth)acrylicester.

Concrete examples of the photoreaction initiator include2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-(dimethylamino)-2[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone,2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide,bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide,bis(η5-2,4-cyclopentadiene-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole-1-yl)-phenyl)titanium,2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone,diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropane-1-one,benzyldimethylketal,4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone,1-hydroxycyclohexylphenylketone,2-methyl-2-morpholino(4-thiomethylphenyl)propane-1-one,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone,2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone oligomer,benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropylether, benzoin isobutyl ether, benzophenone, methyl o-benzoylbenzoate,4-phenylbenzophenone, 4-benzoyl-4′-methyl-diphenylsulfide,3,3′,4,4′-tetra(t-butylperoxycarbonyl)benzophenone,2,4,6-trimethylbenzophenone,4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyloxy)ethyl]benzenemethanaminium bromide, (4-benzoylbenzyl)trimethylammonium chloride,2-isopropylthioxanthone, 4-isopropylthioxanthone,2,4-diethylthioxanthone, 2,4-dichlorothioxanthone,1-chloro-4-propoxythioxanthone,2-(3-dimethylamino-2-hydroxy)-3,4-dimethyl-9H-thioxanthone-9-onemethochloride, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide,bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide,bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, triphenylmethyliumtetrakis(pentafluorophenyl) borate and the like. Only one kind of thephotoreaction initiator may be used, and two or more kinds thereof maybe used in combination.

Examples of the auxiliary include triethanolamine, triisopropanolamine,4,4′-dimethylaminobenzophenone (Michler's ketone),4,4′-diethylaminobenzophenone, 2-dimethylaminoethyl benzoic acid, andethyl 4-dimethylaminobenzoate and the like. Also, examples of theauxiliary include (n-butoxy)ethyl 4-dimethylaminobenzoate, isoamyl4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate,2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone and the like. Onekind of the auxiliary may be used alone and two or more kinds thereofmay be used in combination.

It is preferred that the auxiliary be benzyldimethylketal,1-hydroxycyclohexylphenyl ketone, benzoylisopropyl ether,4-(2-hydroxyethoxy)-phenyl(2-hydroxy-2-propyl) ketone,2-hydroxy-2-methyl-1-phenylpropane-1-one, or triphenylmethyliumtetrakis(pentafluorophenyl) borate.

In 100% by weight of the polymerizable composition, the content of thephotoreaction initiator is preferably 0.01% by weight or more, morepreferably 0.1 parts by weight or more and is preferably 10% by weightor less, more preferably 5% by weight or less. When the content of thephotoreaction initiator is in the range from the above-described lowerlimit to the above-described upper limit, the photocurability and thestorage stability further increase.

It is preferred that the polyvinyl acetate be a polymer of apolymerizable composition containing vinyl acetate and a monomer havingthe above-described functional group because excellent effect of thepresent invention is achieved.

Examples of the monomer having the above-described functional groupinclude 3-methyl-3-buten-1-ol, ethylene glycol monovinyl ether,isopropylacrylamide and the like.

From the viewpoint of effectively enhancing the sound insulatingproperty, the weight average molecular weight of the polyvinyl acetateis preferably 250000 or more, more preferably 300000 or more, furtherpreferably 400000 or more, especially preferably 500000 or more. Fromthe viewpoint of enhancing the interlayer adhesion, the weight averagemolecular weight of the polyvinyl acetate is preferably 1200000 or less,more preferably 900000 or less.

The weight average molecular weight refers to a weight average molecularweight, calculated on the polystyrene equivalent basis, measured by gelpermeation chromatography (GPC).

The method for polymerizing the polymerizable composition to synthesizethe polyvinyl acetate is not particularly limited. Examples of thesynthesizing method include a solution polymerization, suspensionpolymerization, UV polymerization and the like.

From the viewpoint of increasing the transparency of the interlayerfilm, and effectively enhancing the sound insulating property and theinterlayer adhesion in the interlayer film having increasedtransparency, the synthesizing method of the polyvinyl acetate ispreferably solution polymerization.

From the viewpoint of effectively enhancing the sound insulatingproperty, the thermoplastic elastomer is preferably an aliphaticpolyolefin or a styrene elastomer, and is more preferably an aliphaticpolyolefin.

The aliphatic polyolefin may be a saturated aliphatic polyolefin, or maybe an unsaturated aliphatic polyolefin. The aliphatic polyolefin may bea polyolefin composed of a chain olefin as a monomer, or may be apolyolefin composed of a cyclic olefin as a monomer. From the viewpointof effectively enhancing the storage stability and the sound insulatingproperty of the interlayer film, it is preferred that the aliphaticpolyolefin be a saturated aliphatic polyolefin.

Examples of the material for the aliphatic polyolefin include ethylene,propylene, 1-butene, trans-2-butene, cis-2-butene, 1-pentene,trans-2-pentene, cis-2-pentene, 1-hexene, trans-2-hexene, cis-2-hexene,trans-3-hexene, cis-3-hexene, 1-heptene, trans-2-heptene, cis-2-heptene,trans-3-heptene, cis-3-heptene, 1-octene, trans-2-octene, cis-2-octene,trans-3-octene, cis-3-octene, trans-4-octene, cis-4-octene, 1-nonene,trans-2-nonene, cis-2-nonene, trans-3-nonene, cis-3-nonene,trans-4-nonene, cis-4-nonene, 1-decene, trans-2-decene, cis-2-decene,trans-3-decene, cis-3-decene, trans-4-decene, cis-4-decene,trans-5-decene, cis-5-decene, 4-methyl-1-pentene, and vinylcyclohexane.

From the viewpoint of effectively enhancing the sound insulatingproperty, it is preferred that the aliphatic polyolefin have a chainedhydrocarbon group on a side chain.

When the interlayer film has a multilayer structure, the aliphaticpolyolefin may be a modified aliphatic polyolefin from the viewpoint ofimproving the interlayer adhesive strength. It is preferred that themodified aliphatic polyolefin have a carboxyl group, a carboxylicanhydride group, a hydroxyl group or an epoxy group or the like. Themodified aliphatic polyolefin may have these groups on a side chain ofthe molecular chain, or on a terminus.

(Thermoplastic Resin in Second Layer and Third Layer)

From the viewpoint of effectively enhancing the adhesiveness between theinterlayer film and the glass plates, it is preferred that the secondlayer contain a thermoplastic resin (hereinafter, sometimes described asa thermoplastic resin (2)). From the viewpoint of effectively enhancingthe adhesiveness between the interlayer film and the glass plates, it ispreferred that the second layer contain a thermoplastic resin other thanthe thermoplastic resin of the first layer, and it is more preferredthat the second layer contain a polyvinyl acetal resin (hereinafter,sometimes described as polyvinyl acetal resin (2)). From the viewpointof effectively enhancing the adhesiveness, it is preferred that thethird layer contain a thermoplastic resin (hereinafter, sometimesdescribed as a thermoplastic resin (3)). From the viewpoint ofeffectively enhancing the adhesiveness between the interlayer film andthe glass plates, it is preferred that the third layer contain athermoplastic resin other than the thermoplastic resin, and it is morepreferred that the third layer contain a polyvinyl acetal resin(hereinafter, sometimes described as polyvinyl acetal resin (3)).

Examples of the thermoplastic resins (2), (3) include a polyvinyl acetalresin, an ethylene-vinyl acetate copolymer resin, an ethylene-acrylicacid copolymer resin, a polyurethane resin, and a polyvinyl alcoholresin, a polyvinyl acetate resin, a polyester resin, and the like.Thermoplastic resins other than these may be used.

For example, the polyvinyl acetal resin can be produced by acetalizingpolyvinyl alcohol (PVA) with an aldehyde. It is preferred that thepolyvinyl acetal resin be an acetalized product of polyvinyl alcohol.For example, the polyvinyl alcohol can be obtained by saponifyingpolyvinyl acetate. The saponification degree of the polyvinyl alcoholgenerally lies within the range of 70 to 99.9% by mole.

The average polymerization degree of the polyvinyl alcohol (PVA) ispreferably 200 or more, more preferably 500 or more, even morepreferably 1500 or more, further preferably 1600 or more, and ispreferably 5000 or less, more preferably 4000 or less, furtherpreferably 3500 or less, especially preferably 3000 or less. When theaverage polymerization degree is the above lower limit or more, thepenetration resistance of laminated glass is further enhanced. When theaverage polymerization degree is the above upper limit or less,formation of an interlayer film is facilitated.

The average polymerization degree of the polyvinyl alcohol is determinedby a method in accordance with JIS K6726 “Testing methods for polyvinylalcohol”.

The number of carbon atoms of the acetal group contained in thepolyvinyl acetal resin is not particularly limited. The aldehyde used atthe time of producing the polyvinyl acetal resin is not particularlylimited. It is preferred that the number of carbon atoms of the acetalgroup in the polyvinyl acetal resin fall within the range of 3 to 5 andit is more preferred that the number of carbon atoms of the acetal groupbe 3 or 4. When the number of carbon atoms of the acetal group in thepolyvinyl acetal resin is 3 or more, the glass transition temperature ofthe interlayer film is sufficiently lowered.

The aldehyde is not particularly limited. In general, an aldehyde with 1to 10 carbon atoms is preferably used. Examples of the aldehyde with 1to 10 carbon atoms include formaldehyde, acetaldehyde, propionaldehyde,n-butyraldehyde, isobutyraldehyde, n-valeraldehyde,2-ethylbutyraldehyde, n-hexylaldehyde, n-octylaldehyde, nonylaldehyde,n-decylaldehyde, formaldehyde, acetaldehyde, benzaldehyde, and the like.The aldehyde is preferably propionaldehyde, n-butyraldehyde,isobutyraldehyde, n-hexylaldehyde, or n-valeraldehyde, more preferablypropionaldehyde, n-butyraldehyde, or isobutyraldehyde, and furtherpreferably n-butyraldehyde. One kind of the aldehyde may be used alone,and two or more kinds thereof may be used in combination.

The content of the hydroxyl group (the amount of hydroxyl groups) of thepolyvinyl acetal resin is preferably 15% by mole or more, morepreferably 18% by mole or more, and preferably 40% by mole or less, andmore preferably 35% by mole or less. When the content of the hydroxylgroup is the above lower limit or more, the adhesive force of theinterlayer film is further enhanced. Moreover, when the content of thehydroxyl group is the above upper limit or less, the flexibility of theinterlayer film is enhanced and the handling of the interlayer film isfacilitated.

A content of the hydroxyl group (the amount of hydroxyl groups) of thepolyvinyl acetal resin (1) is preferably 17% by mole or more, morepreferably 20% by mole or more, further preferably 22% by mole or moreand is preferably 28% by mole or less, more preferably 27% by mole orless, further preferably 25% by mole or less, especially preferably 24%by mole or less. When the content of the hydroxyl group is the abovelower limit or more, the mechanical strength of the interlayer film isfurther enhanced. In particular, when the content of the hydroxyl groupof the polyvinyl acetal resin (1) is 20% by mole or more, the resin ishigh in reaction efficiency and is excellent in productivity, andmoreover, when being 28% by mole or less, the sound insulating propertyof laminated glass is further enhanced. Moreover, when the content ofthe hydroxyl group is the above upper limit or less, the flexibility ofthe interlayer film is enhanced and the handling of the interlayer filmis facilitated.

Each of the contents of the hydroxyl group of the polyvinyl acetal resin(2) and the polyvinyl acetal resin (3) is preferably 25% by mole ormore, more preferably 28% by mole or more, more preferably 30% by moleor more, still more preferably 31.5% by mole or more, further preferably32% by mole or more, especially preferably 33% by mole or more. Each ofthe contents of the hydroxyl group of the polyvinyl acetal resin (2) andthe polyvinyl acetal resin (3) is preferably 38% by mole or less, morepreferably 37% by mole or less, further preferably 36.3% by mole orless, especially preferably 36% by mole or less. When the content of thehydroxyl group is the above lower limit or more, the adhesive force ofthe interlayer film is further enhanced. Moreover, when the content ofthe hydroxyl group is the above upper limit or less, the flexibility ofthe interlayer film is enhanced and the handling of the interlayer filmis facilitated.

The content of the hydroxyl group of the polyvinyl acetal resin is amole fraction, represented in percentage, obtained by dividing theamount of ethylene groups to which the hydroxyl group is bonded by thetotal amount of ethylene groups in the main chain. For example, theamount of ethylene groups to which the hydroxyl group is bonded can bedetermined in accordance with JIS K6728 “Testing methods for polyvinylbutyral”.

The acetylation degree (the amount of acetyl groups) of the polyvinylacetal resin (1) is preferably 0.01% by mole or more, more preferably0.1% by mole or more, even more preferably 7% by mole or more, furtherpreferably 9% by mole or more and is preferably 30% by mole or less,more preferably 25% by mole or less, further preferably 24% by mole orless, especially preferably 20% by mole or less. When the acetylationdegree is the above lower limit or more, the compatibility between thepolyvinyl acetal resin and a plasticizer is enhanced. When theacetylation degree is the above upper limit or less, with regard to theinterlayer film and laminated glass, the moisture resistance thereof isenhanced. In particular, when the acetylation degree of the polyvinylacetal resin (1) is 0.1% by mole or more and is 25% by mole or less, theresulting laminated glass is excellent in penetration resistance.

The acetylation degree of each of the polyvinyl acetal resin (2) and thepolyvinyl acetal resin (3) is preferably 0.01% by mole or more, and morepreferably 0.5% by mole or more and is preferably 10% by mole or less,and more preferably 2% by mole or less. When the acetylation degree isthe above lower limit or more, the compatibility between the polyvinylacetal resin and a plasticizer is enhanced. When the acetylation degreeis the above upper limit or less, with regard to the interlayer film andlaminated glass, the moisture resistance thereof is enhanced.

The acetylation degree is a mole fraction, represented in percentage,obtained by dividing the amount of ethylene groups to which the acetylgroup is bonded by the total amount of ethylene groups in the mainchain. For example, the amount of ethylene groups to which the acetylgroup is bonded can be determined in accordance with JIS K6728 “Testingmethods for polyvinyl butyral”.

The acetalization degree of the polyvinyl acetal resin (1) (thebutyralization degree in the case of a polyvinyl butyral resin) ispreferably 47% by mole or more and more preferably 60% by mole or moreand is preferably 85% by mole or less, more preferably 80% by mole orless, further preferably 75% by mole or less. When the acetalizationdegree is the above lower limit or more, the compatibility between thepolyvinyl acetal resin and a plasticizer is enhanced. When theacetalization degree is the above upper limit or less, the reaction timerequired for producing the polyvinyl acetal resin is shortened.

The acetalization degree of each of the polyvinyl acetal resin (2) andthe polyvinyl acetal resin (3) (the butyralization degree in the case ofa polyvinyl butyral resin) is preferably 55% by mole or more, and morepreferably 60% by mole or more and is preferably 75% by mole or less,and more preferably 71% by mole or less. When the acetalization degreeis the above lower limit or more, the compatibility between thepolyvinyl acetal resin and a plasticizer is enhanced. When theacetalization degree is the above upper limit or less, the reaction timerequired for producing the polyvinyl acetal resin is shortened.

The acetalization degree is determined in the following manner. From thetotal amount of the ethylene group in the main chain, the amount of theethylene group to which the hydroxyl group is bonded and the amount ofthe ethylene group to which the acetyl group is bonded are subtracted.The obtained value is divided by the total amount of the ethylene groupin the main chain to obtain a mole fraction. The mole fractionrepresented in percentage is the acetalization degree.

In this connection, it is preferred that the content of the hydroxylgroup (the amount of hydroxyl groups), the acetalization degree (thebutyralization degree) and the acetylation degree be calculated from theresults determined by a method in accordance with JIS K6728 “Testingmethods for polyvinyl butyral”. In this context, a method in accordancewith ASTM D1396-92 may also be used. When the polyvinyl acetal resin isa polyvinyl butyral resin, the content of the hydroxyl group (the amountof hydroxyl groups), the acetalization degree (the butyralizationdegree) and the acetylation degree can be calculated from the resultsmeasured by a method in accordance with JIS K6728 “Testing methods forpolyvinyl butyral”.

(Plasticizer)

The resin layer contains a plasticizer. One kind of the plasticizer inthe resin layer may be used alone, and two or more kinds thereof may beused in combination.

From the viewpoint of effectively enhancing the sound insulatingproperty, it is preferred that the first layer contain a plasticizer(hereinafter, sometimes described as a plasticizer (1)). From theviewpoint of effectively enhancing the sound insulating property, it ispreferred that the second layer contain a plasticizer (hereinafter,sometimes described as a plasticizer (2)). From the viewpoint ofeffectively enhancing the sound insulating property, it is preferredthat the third layer contain a plasticizer (hereinafter, sometimesdescribed as a plasticizer (3)). One kind of the plasticizer in theselayers may be used alone, and two or more kinds thereof may be used incombination.

Examples of the plasticizer include paraffin oil, an organic esterplasticizer, and a phosphate plasticizer, and the like. Examples of theorganic ester plasticizer include a monobasic organic acid ester, apolybasic organic acid ester, and the like. Examples of the phosphateplasticizer include an organic phosphate plasticizer and an organicphosphite plasticizer, and the like. It is preferred that theplasticizer be a liquid plasticizer.

Examples of the paraffin oil include naphthenic process oil, whitemineral oil, mineral oil, paraffin wax, liquid paraffin, and the like.

Examples of commercially available paraffin oil include “Diana processoil PW-90” available from Idemitsu Kosan Co., Ltd., “Diana process oilPW-100” available from Idemitsu Kosan Co., Ltd., “Diana process oilPW-32” available from Idemitsu Kosan Co., Ltd., and the like.

Examples of the organic ester plasticizer include triethylene glycoldi-2-ethylpropanoate, triethylene glycol di-2-ethylbutyrate, triethyleneglycol di-2-ethylhexanoate, triethylene glycol dicaprylate, triethyleneglycol di-n-octanoate, triethylene glycol di-n-heptanoate, tetraethyleneglycol di-n-heptanoate, dibutyl sebacate, dioctyl azelate, dibutylcarbitol adipate, ethylene glycol di-2-ethylbutyrate, 1,3-propyleneglycol di-2-ethylbutyrate, 1,4-butylene glycol di-2-ethylbutyrate,diethylene glycol di-2-ethylbutyrate, diethylene glycoldi-2-ethylhexanoate, dipropylene glycol di-2-ethylbutyrate, triethyleneglycol di-2-ethylpentanoate, tetraethylene glycol di-2-ethylbutyrate,diethylene glycol dicaprylate, dibutyl maleate, bis(2-butoxyethyl)adipate, dibutyl adipate, diisobutyl adipate, 2,2-butoxyethoxyethyladipate, benzoic acid glycol ester, adipic acid 1,3-butyleneglycolpolyester, dihexyl adipate, dioctyl adipate, hexyl cyclohexyl adipate, amixture of heptyl adipate and nonyl adipate, diisononyl adipate,diisodecyl adipate, heptyl nonyl adipate, tributyl citrate, tributylacetylcitrate, diethyl carbonate, dibutyl sebacate, oil-modified sebacicalkyds, a mixture of a phosphoric acid ester and an adipic acid ester,and the like. Organic ester plasticizers other than these may be used.Other adipic acid esters other than the above-described adipic acidesters may be used.

Examples of the organic ester plasticizer include a diester plasticizerrepresented by the following structural formula (11).

In the foregoing formula (11), R1 and R2 each represent an organic groupwith 5 to 10 carbon atoms, R3 represents an ethylene group, anisopropylene group or a n-propylene group, and p represents an integerof 3 to 10. It is preferred that R1 and R2 in the foregoing formula (11)each be an organic group with 6 to 10 carbon atoms.

Examples of the organic phosphate plasticizer include tributoxyethylphosphate, isodecyl phenyl phosphate, triisopropyl phosphate, and thelike.

When the resin of the first layer is a thermoplastic elastomer, theplasticizing effect can be low if the organic ester plasticizer is used.When a thermoplastic elastomer is used as the thermoplastic resin of thefirst layer, it is preferred that the plasticizer in the first layer bea plasticizer other than an organic ester plasticizer. When athermoplastic elastomer is used as the thermoplastic resin of the firstlayer, the resonance frequency X and the loss factor Y are easy tosatisfy the aforementioned preferred ranges, and can easily satisfy theabove formula (1) by using a plasticizer other than an organic esterplasticizer as the plasticizer in the first layer. As a result, theeffect of the present invention can be exerted more effectively.

When the resin of the first layer is a thermoplastic elastomer (inparticular, aliphatic polyolefin), it is preferred that the plasticizerin the first layer be a paraffin oil. In this case, it is possible toenhance the sound insulating property.

When the resin of the first layer is polyvinyl acetate, the plasticizerin the first layer is preferably an organic ester plasticizer, and ismore preferably an adipic acid ester. In this case, the resonancefrequency X and the loss factor Y are easy to satisfy the above ranges,and easily satisfy the above formula (1). As a result, the effect of thepresent invention can be exerted more effectively.

When the first layer contains a cured product of a photocurable compoundor a moisture-curable compound (in particular, a curable compound havinga (meth)acryloyl group), it is preferred that the plasticizer in thefirst layer be an organic ester plasticizer. In this case, the resonancefrequency X and the loss factor Y are easy to satisfy the above ranges,and easily satisfy the above formula (1). As a result, the effect of thepresent invention can be exerted more effectively.

From the viewpoint of effectively enhancing the adhesiveness between theglass plates and the interlayer film, it is preferred that each of theplasticizer in the second layer and the plasticizer in the third layerbe an organic ester plasticizer, and it is more preferred that each ofthe plasticizer in the second layer and the plasticizer in the thirdlayer be a diester plasticizer represented by the above formula (11).From the viewpoint of effectively enhancing the adhesiveness between theglass plates and the interlayer film, it is preferred that each of theplasticizer in the second layer and the plasticizer in the third layercontain triethylene glycol di-2-ethylhexanoate (3GO) or triethyleneglycol di-2-ethylbutyrate (3GH). From the viewpoint of effectivelyenhancing the adhesiveness between the glass plates and the interlayerfilm, it is more preferred that triethylene glycol di-2-ethylhexanoatebe contained.

In the first layer, the content of the plasticizer relative to 100 partsby weight of the resin (1) is referred to as content (1). When the resin(1) is the thermoplastic resin (1), 100 parts by weight of the resin (1)is 100 parts by weight of the thermoplastic resin (1). From theviewpoint of effectively enhancing the sound insulating property, thecontent (1) is preferably 10 parts by weight or more, more preferably 20parts by weight or more, and is preferably 60 parts by weight or less,more preferably 50 parts by weight or less. When the content (1) is theabove lower limit or more, it is possible to effectively enhance thesound insulating property. When the content (1) is the above upper limitor less, the penetration resistance of laminated glass is furtherenhanced.

When the resin (thermoplastic resin) of the first layer is athermoplastic elastomer, the content (1) is preferably 20 parts byweight or more, more preferably 25 parts by weight or more, and ispreferably 45 parts by weight or less, more preferably 40 parts byweight or less. When the content (1) is the above lower limit or moreand the above upper limit or less, the resonance frequency X and theloss factor Y are easy to satisfy the above ranges, and easily satisfythe above formula (1). As a result, the effect of the present inventioncan be exerted more effectively.

When the resin (thermoplastic resin) of the first layer is polyvinylacetate, the content (1) is preferably 30 parts by weight or more, morepreferably 35 parts by weight or more, and is preferably 100 parts byweight or less, more preferably 90 parts by weight or less. In the casewhere polyvinyl acetate is used as the resin of the first layer, theresonance frequency X and the loss factor Y are easy to satisfy theabove ranges, and easily satisfy the above formula (1) when the content(1) is the above lower limit or more and the above upper limit or less.As a result, the effect of the present invention can be exerted moreeffectively.

When the first layer contains a cured product of a photocurable compoundor a moisture-curable compound (in particular, a curable compound havinga (meth)acryloyl group), the content (1) is preferably 15 parts byweight or more, more preferably 20 parts by weight or more, and ispreferably 60 parts by weight or less, more preferably 50 parts byweight or less. In the case where a photocurable compound or amoisture-curable compound is used as the resin of the first layer, theresonance frequency X and the loss factor Y are easy to satisfy theabove ranges, and easily satisfy the above formula (1) when the content(1) is the above lower limit or more and the above upper limit or less.As a result, the effect of the present invention can be exerted moreeffectively.

In the second layer, the content of the plasticizer (2) relative to 100parts by weight of the thermoplastic resin (2) is referred to as content(2). In the third layer, the content of the plasticizer (3) relative to100 parts by weight of the thermoplastic resin (3) is referred to ascontent (3). Each of the content (2) and the content (3) is preferably10 parts by weight or more, more preferably 15 parts by weight or more,further preferably 20 parts by weight or more, especially preferably 24parts by weight or more, most preferably 25 parts by weight or more, andis preferably 45 parts by weight or less, more preferably 40 parts byweight or less. When the content (2) and the content (3) are the abovelower limit or more, the flexibility of the interlayer film is enhancedand the handling of the interlayer film is facilitated. When the content(2) and the content (3) are the above upper limit or less, thepenetration resistance of laminated glass is further enhanced.

(Heat Shielding Substance)

The interlayer film may contain a heat shielding substance (heatshielding compound). The first layer may contain a heat shieldingsubstance. The second layer may contain a heat shielding substance. Thethird layer may contain a heat shielding substance. One kind of the heatshielding substance may be used alone, and two or more kinds thereof maybe used in combination.

It is preferred that the heat shielding substance contain at least onekind of Ingredient X among a phthalocyanine compound, a naphthalocyaninecompound, and an anthracyanine compound or contain heat shieldingparticles. In this case, the heat shielding compound may be constitutedof both of the Ingredient X and the heat shielding particles.

Ingredient X:

The interlayer film may contain at least one kind of Ingredient X amonga phthalocyanine compound, a naphthalocyanine compound and ananthracyanine compound. The first layer may contain the Ingredient X.The second layer may contain the Ingredient X. The third layer maycontain the Ingredient X. The Ingredient X is a heat shieldingsubstance. One kind of the Ingredient X may be used alone, and two ormore kinds thereof may be used in combination.

The Ingredient X is not particularly limited. As the Ingredient X,conventionally known phthalocyanine compound, naphthalocyanine compoundand anthracyanine compound can be used.

Examples of the Ingredient X include phthalocyanine, a derivative ofphthalocyanine, naphthalocyanine, a derivative of naphthalocyanine,anthracyanine, and a derivative of anthracyanine, and the like. It ispreferred that each of the phthalocyanine compound and the derivative ofphthalocyanine have a phthalocyanine skeleton. It is preferred that eachof the naphthalocyanine compound and the derivative of naphthalocyaninehave a naphthalocyanine skeleton. It is preferred that each of theanthracyanine compound and the derivative of anthracyanine have ananthracyanine skeleton.

With regard to the interlayer film and laminated glass, from theviewpoint of further enhancing the heat shielding properties thereof, itis preferred that the Ingredient X be at least one kind selected fromthe group consisting of phthalocyanine, a derivative of phthalocyanine,naphthalocyanine and a derivative of naphthalocyanine, and it is morepreferred that the Ingredient X be at least one kind amongphthalocyanine and a derivative of phthalocyanine.

From the viewpoints of effectively enhancing the heat shieldingproperties and maintaining the visible light transmittance at a higherlevel over a long period of time, it is preferred that the Ingredient Xcontain vanadium atoms or copper atoms. It is preferred that theIngredient X contain vanadium atoms and it is also preferred that theIngredient X contain copper atoms. It is more preferred that theIngredient X be at least one kind among phthalocyanine containingvanadium atoms or copper atoms and a derivative of phthalocyaninecontaining vanadium atoms or copper atoms. With regard to the interlayerfilm and laminated glass, from the viewpoint of still further enhancingthe heat shielding properties thereof, it is preferred that theIngredient X have a structural unit in which an oxygen atom is bonded toa vanadium atom.

In 100% by weight of the interlayer film or in 100% by weight of a layercontaining the Ingredient X (a first layer, a second layer, or a thirdlayer), the content of the Ingredient X is preferably 0.001% by weightor more, more preferably 0.005% by weight or more, further preferably0.01% by weight or more, especially preferably 0.02% by weight or more.In 100% by weight of the interlayer film or in 100% by weight of a layercontaining the Ingredient X (a first layer, a second layer, or a thirdlayer), the content of the Ingredient X is preferably 0.2% by weight orless, more preferably 0.1% by weight or less, further preferably 0.05%by weight or less, especially preferably 0.04% by weight or less. Whenthe content of the Ingredient X is the above lower limit or more and theabove upper limit or less, the heat shielding properties aresufficiently enhanced and the visible light transmittance issufficiently enhanced. For example, it is possible to make the visiblelight transmittance 70% or more.

Heat Shielding Particles:

The interlayer film may contain heat shielding particles. The firstlayer may contain heat shielding particles. The second layer may containheat shielding particles. The third layer may contain heat shieldingparticles. The heat shielding particle is of a heat shielding substance.By the use of heat shielding particles, infrared rays (heat rays) can beeffectively cut off. One kind of the heat shielding particles may beused alone, and two or more kinds thereof may be used in combination.

From the viewpoint of further enhancing the heat shielding properties oflaminated glass, it is more preferred that the heat shielding particlesbe metal oxide particles. It is preferred that the heat shieldingparticle be a particle (a metal oxide particle) formed from an oxide ofa metal.

The energy amount of an infrared ray with a wavelength of 780 nm orlonger which is longer than that of visible light is small as comparedwith an ultraviolet ray. However, the thermal action of infrared rays islarge, and when infrared rays are absorbed into a substance, heat isreleased from the substance. Accordingly, infrared rays are generallycalled heat rays. By the use of the heat shielding particles, infraredrays (heat rays) can be effectively cut off. In this connection, theheat shielding particle means a particle capable of absorbing infraredrays.

Specific examples of the heat shielding particles include metal oxideparticles such as aluminum-doped tin oxide particles, indium-doped tinoxide particles, antimony-doped tin oxide particles (ATO particles),gallium-doped zinc oxide particles (GZO particles), indium-doped zincoxide particles (IZO particles), aluminum-doped zinc oxide particles(AZO particles), niobium-doped titanium oxide particles, sodium-dopedtungsten oxide particles, cesium-doped tungsten oxide particles,thallium-doped tungsten oxide particles, rubidium-doped tungsten oxideparticles, tin-doped indium oxide particles (ITO particles), tin-dopedzinc oxide particles and silicon-doped zinc oxide particles, lanthanumhexaboride (LaB₆) particles, and the like. Heat shielding particlesother than these may be used. Since the heat ray shielding function ishigh, preferred are metal oxide particles, more preferred are ATOparticles, GZO particles, IZO particles, ITO particles or tungsten oxideparticles, and especially preferred are ITO particles or tungsten oxideparticles. In particular, since the heat ray shielding function is highand the particles are readily available, preferred are tin-doped indiumoxide particles (ITO particles), and also preferred are tungsten oxideparticles.

With regard to the interlayer film and laminated glass, from theviewpoint of further enhancing the heat shielding properties thereof, itis preferred that the tungsten oxide particles be metal-doped tungstenoxide particles. Examples of the “tungsten oxide particles” includemetal-doped tungsten oxide particles. Specifically, examples of themetal-doped tungsten oxide particles include sodium-doped tungsten oxideparticles, cesium-doped tungsten oxide particles, thallium-dopedtungsten oxide particles, rubidium-doped tungsten oxide particles, andthe like.

With regard to the interlayer film and laminated glass, from theviewpoint of further enhancing the heat shielding properties thereof,cesium-doped tungsten oxide particles are especially preferred. Withregard to the interlayer film and laminated glass, from the viewpoint ofstill further enhancing the heat shielding properties thereof, it ispreferred that the cesium-doped tungsten oxide particles be tungstenoxide particles represented by the formula: Cs_(0.33)WO₃.

The average particle diameter of the heat shielding particles ispreferably 0.01 μm or more, more preferably 0.02 μm or more, and ispreferably 0.1 μm or less, more preferably 0.05 μm or less. When theaverage particle diameter is the above lower limit or more, the heat rayshielding properties are sufficiently enhanced. When the averageparticle diameter is the above upper limit or less, the dispersibilityof heat shielding particles is enhanced.

The “average particle diameter” refers to the volume average particlediameter. The average particle diameter can be measured using a particlesize distribution measuring apparatus (“UPA-EX150” available fromNIKKISO CO., LTD.), or the like.

In 100% by weight of the interlayer film or in 100% by weight of a layercontaining the heat shielding particles (a first layer, a second layer,or a third layer), the content of the heat shielding particles ispreferably 0.01% by weight or more, more preferably 0.1% by weight ormore, further preferably 1% by weight or more, especially preferably1.5% by weight or more. In 100% by weight of the interlayer film, or in100% by weight of a layer containing the heat shielding particles (afirst layer, a second layer, or a third layer), the content of the heatshielding particles is preferably 6% by weight or less, more preferably5.5% by weight or less, further preferably 4% by weight or less,especially preferably 3.5% by weight or less, most preferably 3% byweight or less. When the content of the heat shielding particles is theabove lower limit or more and the above upper limit or less, the heatshielding properties are sufficiently enhanced and the visible lighttransmittance is sufficiently enhanced.

(Metal Salt)

The interlayer film may contain an alkali metal salt, an alkali earthmetal salt, or a magnesium salt (hereinafter, these are sometimesdescribed as Metal salt M). The first layer may contain the Metal saltM. The second layer may contain the metal salt M. The third layer maycontain the Metal salt M. By the use of the Metal salt M, controllingthe adhesivity between the interlayer film and a lamination glass membersuch as a glass plate or the adhesivity between respective layers in theinterlayer film is facilitated. One kind of the Metal salt M may be usedalone, and two or more kinds thereof may be used in combination.

It is preferred that the Metal salt M contain as metal Li, Na, K, Rb,Cs, Mg, Ca, Sr or Ba. It is preferred that the metal salt included inthe interlayer film contain a K salt or Mg salt.

Moreover, it is more preferred that the Metal salt M be an alkali metalsalt of an organic acid with 2 to 16 carbon atoms, an alkaline earthmetal salt of an organic acid with 2 to 16 carbon atoms, and a magnesiumsalt of an organic acid with 2 to 16 carbon atoms, and it is furtherpreferred that the Metal salt M be a magnesium carboxylate with 2 to 16carbon atoms or a potassium carboxylate with 2 to 16 carbon atoms.

The magnesium carboxylate with 2 to 16 carbon atoms and the potassiumcarboxylate with 2 to 16 carbon atoms are not particularly limited.Examples of these include magnesium acetate, potassium acetate,magnesium propionate, potassium propionate, magnesium 2-ethylbutyrate,potassium 2-ethylbutanoate, magnesium 2-ethylhexanoate, potassium2-ethylhexanoate, and the like.

The total of the contents of Mg and K in an interlayer film containingthe Metal salt M or a layer containing the Metal salt M (a first layer,a second layer, or a third layer) is preferably 5 ppm or more, morepreferably 10 ppm or more, and further preferably 20 ppm or more. Thetotal of the contents of Mg and K in an interlayer film containing theMetal salt M or a layer containing the Metal salt M (a first layer, asecond layer, or a third layer) is preferably 300 ppm or less, morepreferably 250 ppm or less, and further preferably 200 ppm or less. Whenthe total of the contents of Mg and K is the above lower limit or moreand the above upper limit or less, the adhesivity between the interlayerfilm and a glass plate or the adhesivity between respective layers inthe interlayer film can be further well controlled.

(Ultraviolet Ray Screening Agent)

The interlayer film may contain an ultraviolet ray screening agent. Thefirst layer may contain an ultraviolet ray screening agent. The secondlayer may contain an ultraviolet ray screening agent. The third layermay contain an ultraviolet ray screening agent. By the use of anultraviolet ray screening agent, even when the interlayer film and thelaminated glass are used for a long period of time, the visible lighttransmittance becomes further hard to be lowered. One kind of theultraviolet ray screening agent may be used alone, and two or more kindsthereof may be used in combination.

Examples of the ultraviolet ray screening agent include an ultravioletray absorber. It is preferred that the ultraviolet ray screening agentbe an ultraviolet ray absorber.

Examples of the ultraviolet ray screening agent include an ultravioletray screening agent containing a metal atom, an ultraviolet rayscreening agent containing a metal oxide, an ultraviolet ray screeningagent having a benzotriazole structure (a benzotriazole compound), anultraviolet ray screening agent having a benzophenone structure (abenzophenone compound), an ultraviolet ray screening agent having atriazine structure (a triazine compound), an ultraviolet ray screeningagent having a malonic acid ester structure (a malonic acid estercompound), an ultraviolet ray screening agent having an oxanilidestructure (an oxanilide compound), an ultraviolet ray screening agenthaving a benzoate structure (a benzoate compound), and the like.

Examples of the ultraviolet ray screening agent containing a metal atominclude platinum particles, particles in which the surface of platinumparticles is coated with silica, palladium particles, particles in whichthe surface of palladium particles is coated with silica, and the like.It is preferred that the ultraviolet ray screening agent not be heatshielding particles.

The ultraviolet ray screening agent is preferably an ultraviolet rayscreening agent having a benzotriazole structure, an ultraviolet rayscreening agent having a benzophenone structure, an ultraviolet rayscreening agent having a triazine structure, or an ultraviolet rayscreening agent having a benzoate structure. The ultraviolet rayscreening agent is more preferably an ultraviolet ray screening agenthaving a benzotriazole structure or an ultraviolet ray screening agenthaving a benzophenone structure, and is further preferably anultraviolet ray screening agent having a benzotriazole structure.

Examples of the ultraviolet ray screening agent containing a metal oxideinclude zinc oxide, titanium oxide, cerium oxide, and the like.Furthermore, with regard to the ultraviolet ray screening agentcontaining a metal oxide, the surface thereof may be coated with anymaterial. Examples of the coating material for the surface of theultraviolet ray screening agent containing a metal oxide include aninsulating metal oxide, a hydrolyzable organosilicon compound, asilicone compound, and the like.

Examples of the insulating metal oxide include silica, alumina,zirconia, and the like. For example, the insulating metal oxide has aband-gap energy of 5.0 eV or more.

Examples of the ultraviolet ray screening agent having a benzotriazolestructure include 2-(2′-hydroxy-5′-methylphenyl)benzotriazole (“TinuvinP” available from BASF Japan Ltd.),2-(2′-hydroxy-3′,5′-di-t-butylphenyl)benzotriazole (“Tinuvin 320”available from BASF Japan Ltd.),2-(2′-hydroxy-3′-t-butyl-5-methylphenyl)-5-chlorobenzotriazole (“Tinuvin326” available from BASF Japan Ltd.),2-(2′-hydroxy-3′,5′-di-amylphenyl)benzotriazole (“Tinuvin 328” availablefrom BASF Japan Ltd.), and the like. It is preferred that theultraviolet ray screening agent be an ultraviolet ray screening agenthaving a benzotriazole structure containing a halogen atom, and it ismore preferred that the ultraviolet ray screening agent be anultraviolet ray screening agent having a benzotriazole structurecontaining a chlorine atom, because those are excellent in ultravioletray screening performance.

Examples of the ultraviolet ray screening agent having a benzophenonestructure include octabenzone (“Chimassorb 81” available from BASF JapanLtd.), and the like.

Examples of the ultraviolet ray screening agent having a triazinestructure include “LA-F70” available from ADEKA CORPORATION,2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]-phenol (“Tinuvin1577FF” available from BASF Japan Ltd.), and the like.

Examples of the ultraviolet ray screening agent having a malonic acidester structure include dimethyl 2-(p-methoxybenzylidene)malonate,tetraethyl-2,2-(1,4-phenylenedimethylidene)bismalonate,2-(p-methoxybenzylidene)-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)malonate,and the like.

Examples of a commercial product of the ultraviolet ray screening agenthaving a malonic acid ester structure include Hostavin B-CAP, HostavinPR-25 and Hostavin PR-31 (any of these is available from Clariant JapanK.K.).

Examples of the ultraviolet ray screening agent having an oxanilidestructure include a kind of oxalic acid diamide having a substitutedaryl group and the like on the nitrogen atom such asN-(2-ethylphenyl)-N′-(2-ethoxy-5-t-butylphenyl)oxalic acid diamide,N-(2-ethylphenyl)-N′-(2-ethoxy-phenyl)oxalic acid diamide and2-ethyl-2′-ethoxy-oxanilide (“Sanduvor VSU” available from ClariantJapan K.K.).

Examples of the ultraviolet ray screening agent having a benzoatestructure include2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate (“Tinuvin120” available from BASF Japan Ltd.), and the like.

In 100% by weight of a layer containing the ultraviolet ray screeningagent (a first layer, a second layer, or a third layer), the content ofthe ultraviolet ray screening agent is preferably 0.1% by weight ormore, more preferably 0.2% by weight or more, further preferably 0.3% byweight or more, especially preferably 0.5% by weight or more. In 100% byweight of a layer containing the ultraviolet ray screening agent (afirst layer, a second layer, or a third layer), the content of theultraviolet ray screening agent is preferably 2.5% by weight or less,more preferably 2% by weight or less, further preferably 1% by weight orless, especially preferably 0.8% by weight or less. When the content ofthe ultraviolet ray screening agent is the above-described lower limitor more and the above-described upper limit or less, deterioration invisible light transmittance after a lapse of a period is furthersuppressed. In particular, by setting the content of the ultraviolet rayscreening agent to be 0.2% by weight or more in 100% by weight of alayer containing the ultraviolet ray screening agent, with regard to alaminate containing a resin film and glass plates, the lowering invisible light transmittance thereof after the lapse of a certain periodof time can be significantly suppressed.

(Oxidation Inhibitor)

The interlayer film may contain an oxidation inhibitor. The first layermay contain an oxidation inhibitor. The second layer may contain anoxidation inhibitor. The third layer may contain an oxidation inhibitor.One kind of the oxidation inhibitor may be used alone, and two or morekinds thereof may be used in combination.

Examples of the oxidation inhibitor include a phenol-based oxidationinhibitor, a sulfur-based oxidation inhibitor, a phosphorus-basedoxidation inhibitor, and the like. The phenol-based oxidation inhibitoris an oxidation inhibitor having a phenol skeleton. The sulfur-basedoxidation inhibitor is an oxidation inhibitor containing a sulfur atom.The phosphorus-based oxidation inhibitor is an oxidation inhibitorcontaining a phosphorus atom.

It is preferred that the oxidation inhibitor be a phenol-based oxidationinhibitor or a phosphorus-based oxidation inhibitor.

Examples of the phenol-based oxidation inhibitor include2,6-di-t-butyl-p-cresol (BHT), butyl hydroxyanisole (BHA),2,6-di-t-butyl-4-ethylphenol, stearylβ-(3,5-di-t-butyl-4-hydroxyphenyl)propionate,2,2′-methylenebis-(4-methyl-6-butylphenol),2,2′-methylenebis-(4-ethyl-6-t-butylphenol),4,4′-butylidene-bis-(3-methyl-6-t-butylphenol),1,1,3-tris-(2-methyl-hydroxy-5-t-butylphenyl)butane,tetrakis[methylene-3-(3′,5′-butyl-4-hydroxyphenyl)propionate]methane,1,3,3-tris-(2-methyl-4-hydroxy-5-t-butylphenol)butane,1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene,bis(3,3′-t-butylphenol)butyric acid glycol ester,bis(3-t-butyl-4-hydroxy-5-methylbenzenepropanoicacid)ethylenebis(oxyethylene), and the like. One kind or two or morekinds among these oxidation inhibitors are preferably used.

Examples of the phosphorus-based oxidation inhibitor include tridecylphosphite, tris(tridecyl) phosphite, triphenyl phosphite, trinonylphenylphosphite, bis(tridecyl)pentaerithritol diphosphite,bis(decyl)pentaerithritol diphosphite, tris(2,4-di-t-butylphenyl)phosphite, bis(2,4-di-t-butyl-6-methylphenyl)ethyl ester phosphorousacid,2,2′-methylenebis(4,6-di-t-butyl-1-phenyloxy)(2-ethylhexyloxy)phosphorus,and the like. One kind or two or more kinds among these oxidationinhibitors are preferably used.

Examples of a commercial product of the oxidation inhibitor include“IRGANOX 245” available from BASF Japan Ltd., “IRGAFOS 168” availablefrom BASF Japan Ltd., “IRGAFOS 38” available from BASF Japan Ltd.,“Sumilizer BHT” available from Sumitomo Chemical Co., Ltd., “H-BHT”available from Sakai Chemical Industry Co., Ltd., “IRGANOX 1010”available from BASF Japan Ltd., and the like.

With regard to the interlayer film and laminated glass, in order tomaintain high visible light transmittance thereof over a long period oftime, it is preferred that the content of the oxidation inhibitor be0.1% by weight or more in 100% by weight of the interlayer film or in100% by weight of the layer containing the oxidation inhibitor (a firstlayer, a second layer or a third layer). Moreover, since an effectcommensurate with the addition of an oxidation inhibitor is notattained, it is preferred that the content of the oxidation inhibitor be2% by weight or less in 100% by weight of the interlayer film or in 100%by weight of the layer containing the oxidation inhibitor.

(Other Ingredients)

Each of the interlayer film, the first layer, the second layer, and thethird layer may contain other ingredient as necessary. Examples of theother ingredient include a coupling agent, a dispersing agent, asurfactant, a flame retardant, an antistatic agent, a pigment, a dye, anadhesive strength adjusting agent (other than metal salt) for between alamination glass member and a layer being in contact with the laminationglass member, an interlayer adhesive strength adjusting agent (otherthan metal salt) a moisture-resistance agent, a fluorescent brighteningagent, and an infrared ray absorber. One kind of the other ingredientmay be used alone, and two or more kinds thereof may be used incombination.

(Other Details of Interlayer Film for Laminated Glass)

The thickness of the interlayer film is not particularly limited. Fromthe viewpoint of the practical aspect and the viewpoint of sufficientlyenhancing the penetration resistance and the flexural rigidity oflaminated glass, the thickness of the interlayer film is preferably 0.1mm or more, more preferably 0.25 mm or more, and is preferably 3 mm orless, more preferably 1.5 mm or less. When the thickness of theinterlayer film is the above lower limit or more, the penetrationresistance and the flexural rigidity of laminated glass are furtherenhanced. When the thickness of the interlayer film is the above upperlimit or less, the transparency of the interlayer film is furtherimproved.

The thickness of the interlayer film (thickness of the entire interlayerfilm) is referred to as T. The thickness of each of the resin layer andthe first layer is preferably 0.035T or more, more preferably 0.0625T ormore, further preferably 0.1T or more and is preferably 0.4T or less,more preferably 0.375T or less, further preferably 0.25T or less,particularly preferably 0.15T or less. When the thickness of the resinlayer and the first layer is 0.4T or less, the flexural rigidity isfurther improved.

The thickness of each of the second layer and the third layer ispreferably 0.3T or more, more preferably 0.3125T or more, furtherpreferably 0.375T or more and is preferably 0.97T or less, morepreferably 0.9375T or less, further preferably 0.9T or less. Thethickness of each of the second layer and the third layer may be0.46875T or less, and may be 0.45T or less. When the thickness of eachof the second layer and the third layer is the above-described lowerlimit or more and the above-described upper limit or less, the rigidityand the sound insulating property of the laminated glass are furtherenhanced.

A total thickness of the second layer and the third layer is preferably0.625T or more, more preferably 0.75T or more, further preferably 0.85Tor more and is preferably 0.97T or less, more preferably 0.9375T orless, further preferably 0.9T or less. When the total thickness of thesecond layer and the third layer is the above-described lower limit ormore and the above-described upper limit or less, the rigidity and thesound insulating property of the laminated glass are further enhanced.

The interlayer film may be an interlayer film having a uniformthickness, and may be an interlayer film having varying thickness. Thesectional shape of the interlayer film may be a rectangular shape andmay be a wedge-like shape. The interlayer film may be wound, and theinterlayer film may be made into a roll body.

The production method of the interlayer film according to the presentinvention is not particularly limited. In the case of a single-layeredinterlayer film, examples of the production method of the interlayerfilm according to the present invention include a method of extruding aresin composition with an extruder. In the case of a multi-layeredinterlayer film, examples of the production method of the interlayerfilm according to the present invention include a method of separatelyforming resin compositions used for constituting respective layers intorespective layers, and then, for example, layering the obtained layers,a method of coextruding resin compositions used for constitutingrespective layers with an extruder and layering the layers, and thelike. From the viewpoint of effectively enhancing the adhesivenessbetween layers of the interlayer film, a method of laminating aftersubjecting the first layer to a plasma treatment or a corona treatmentcan be recited. In the method of laminating after subjecting the firstlayer to a plasma treatment or a corona treatment, the resonancefrequency X and the loss factor Y are easy to satisfy the above ranges,and easily satisfy the above formula (1). As a result, the effect of thepresent invention can be exerted more effectively. Also from theviewpoint of increasing the continuous productivity, a production methodof extrusion-molding is preferred.

It is preferred that the second layer and the third layer contain thesame polyvinyl acetal resin. This case realizes excellent productionefficiency of the interlayer film. For the reason of excellentproduction efficiency of the interlayer film, it is preferred that thesecond layer and the third layer contain the same polyvinyl acetal resinand the same plasticizer. For the reason of excellent productionefficiency of the interlayer film, it is further preferred that thesecond layer and the third layer be formed of the same resincomposition.

It is preferred that the interlayer film have protrusions and recesseson at least one surface of the surfaces of both sides. It is morepreferred that the interlayer film have protrusions and recesses onsurfaces of both sides. Examples of the method for forming theprotrusions and recesses include, but are not particularly limited to, alip emboss method, an emboss roll method, a calender roll method, and aprofile extrusion method. The emboss roll method is preferred because alarge number of embosses of the protrusions and recesses, which is aquantitatively constant protrusion and recess pattern, can be formed.

(Laminated Glass)

FIG. 3 is a sectional view schematically showing an example of laminatedglass prepared with the interlayer film for laminated glass shown inFIG. 1.

A laminated glass 31 shown in FIG. 3 includes a first lamination glassmember 21, a second lamination glass member 22 and the interlayer film11, The interlayer film 11 is arranged between the first laminationglass member 21 and the second lamination glass member 22 to besandwiched therebetween.

The first lamination glass member 21 is layered on a first surface 11 aof the interlayer film 11. The second lamination glass member 22 islayered on a second surface 11 b opposite to the first surface 11 a ofthe interlayer film 11. The first lamination glass member 21 is layeredon an outer surface 2 a of the second layer 2. The second laminationglass member 22 is layered on an outer surface 3 a of a third layer 3.

FIG. 4 is a sectional view schematically showing an example of laminatedglass prepared with the interlayer film for laminated glass shown inFIG. 2.

A laminated glass 31A shown in FIG. 4 includes the first laminationglass member 21, the second lamination glass member 22 and theinterlayer film 11A. The interlayer film 11A is arranged between thefirst lamination glass member 21 and the second lamination glass member22 to be sandwiched therebetween.

The first lamination glass member 21 is layered on the first surface 11a of the interlayer film 11A. The second lamination glass member 22 islayered on the second surface 11 b opposite to the first surface 11 a ofthe interlayer film 11A.

As described above, the laminated glass according to the presentinvention includes a first lamination glass member, a second laminationglass member, and an interlayer film, and the interlayer film is theinterlayer film for laminated glass according to the present invention.In the laminated glass according to the present invention, theabove-mentioned interlayer film is arranged between the first laminationglass member and the second lamination glass member.

It is preferred that the first lamination glass member be the firstglass plate. It is preferred that the second lamination glass member bethe second glass plate.

Examples of the lamination glass member include a glass plate, a PET(polyethylene terephthalate) film, and the like. As the laminated glass,laminated glass in which an interlayer film is sandwiched between aglass plate and a PET film or the like, as well as laminated glass inwhich an interlayer film is sandwiched between two glass plates, isincluded. The laminated glass is a laminate provided with a glass plate,and it is preferred that at least one glass plate be used. It ispreferred that each of the first lamination glass member and the secondlamination glass member be a glass plate or a PET film, and thelaminated glass be provided with a glass plate as at least one among thefirst lamination glass member and the second lamination glass member.

Examples of the glass plate include a sheet of inorganic glass and asheet of organic glass. Examples of the inorganic glass include floatplate glass, heat ray-absorbing plate glass, heat ray-reflecting plateglass, polished plate glass, figured glass, wired plate glass, and thelike. The organic glass is synthetic resin glass substituted forinorganic glass. Examples of the organic glass include a polycarbonateplate, a poly(meth)acrylic resin plate, and the like. Examples of thepoly(meth)acrylic resin plate include a polymethyl (meth)acrylate plate,and the like.

The thickness of the lamination glass member is preferably 1 mm or more,more preferably 1.8 mm or more, further preferably 2 mm or more,especially preferably 2.1 mm or more and is preferably 5 mm or less,more preferably 3 mm or less. When the lamination glass member is aglass plate, the thickness of the glass plate is preferably 1 mm ormore, more preferably 1.8 mm or more, further preferably 2 mm or more,especially preferably 2.1 mm or more and is preferably 5 mm or less,more preferably 3 mm or less, further preferably 2.6 mm or less. Whenthe lamination glass member is a PET film, the thickness of the PET filmis preferably 0.03 mm or more and is preferably 0.5 mm or less.

The method for producing the laminated glass is not particularlylimited. First, the interlayer film is sandwiched between the firstlamination glass member and the second lamination glass member to obtaina laminate. Then, for example, by passing the obtained laminate throughpressure rolls or subjecting the obtained laminate to decompressionsuction in a rubber bag, the air remaining between the first and thesecond lamination glass members and the interlayer film is removed.Then, the laminate is preliminarily bonded together at about 70 to 110°C. to obtain a preliminarily press-bonded laminate. Next, by putting thepreliminarily press-bonded laminate into an autoclave or by pressing thelaminate, the laminate is press-bonded at about 120 to 150° C. and undera pressure of 1 to 1.5 MPa. In this way, laminated glass can beobtained. At the time of producing the laminated glass, a first layer, asecond layer, and a third layer may be layered.

Each of the interlayer film and the laminated glass can be used forautomobiles, railway vehicles, aircraft, ships, buildings, and the like.Each of the interlayer film and the laminated glass can also be used forapplications other than these applications. It is preferred that theinterlayer film and the laminated glass be an interlayer film andlaminated glass for vehicles or for building respectively, and it ismore preferred that the interlayer film and the laminated glass be aninterlayer film and laminated glass for vehicles respectively. Each ofthe interlayer film and the laminated glass can be used for awindshield, side glass, rear glass, or roof glass of an automobile, andthe like. The interlayer film and the laminated glass are suitably usedfor automobiles. The interlayer film is used for obtaining laminatedglass of an automobile.

Hereinafter, the present invention will be described in more detail withreference to examples and comparative examples. The present invention isnot limited only to these examples.

Example 1 Preparation of Composition for Forming First Layer:

The following ingredients were mixed, and kneaded sufficiently with amixing roll to obtain a composition for forming a first layer.

Aliphatic polyolefin (“ABSORTOMER EP-1001” available from MitsuiChemicals, Inc.; thermoplastic elastomer) 100 parts by weight

Paraffin oil (“Diana process oil PW-90” available from Idemitsu KosanCo., Ltd.) 40 parts by weight

Adhesive strength adjusting agent for between layer and glass plate(“ARUFON UH-2041” available from TOAGOSEI CO., LTD.) 5 parts by weight

An amount that is 0.2% by weight in the obtained interlayer film of anultraviolet ray screening agent(2-(2-hydroxy-3-t-butyl-5-methylphenyl)-5-chlorobenzotriazole)

An amount that is 0.2% by weight in the obtained interlayer film of anoxidation inhibitor (2,6-di-t-butyl-p-cresol)

By extruding the obtained composition for forming the first layer withan extruder, a single-layered interlayer film (thermoplastic elastomerinterlayer film, thickness: 800 μm) was prepared.

Preparation of Laminated Glass (for Measuring Sound InsulatingProperty):

The obtained interlayer film was cut into a size of 25 mm wide and 300mm long. As the first lamination glass member, and the second laminationglass member, two glass plates (clear float glass, 25 mm wide, 300 mmlong and 2 mm thick) were prepared. The interlayer film was sandwichedbetween the two glass plates to obtain a laminate. The laminate was putinto a rubber bag and the interior of the bag was degassed for 20minutes with a degree of vacuum of 2.6 kPa, after which the laminate inthe degassed condition was transferred into an oven, and vacuum-pressedby retention at 90° C. for 30 minutes, and thus the laminate waspreliminarily press-bonded. The preliminarily press-bonded laminate wassubjected to press-bonding for 20 minutes under conditions of 135° C.and a pressure of 1.2 MPa in an autoclave to obtain a sheet of laminatedglass.

Example 2 Preparation of Interlayer Film:

Aliphatic polyolefin (“ABSORTOMER EP-1001” available from MitsuiChemicals, Inc.; thermoplastic elastomer) was dissolved in toluene in aconcentration of 25% by weight to obtain a toluene solution. To thetoluene solution, 35 parts by weight of paraffin oil (“Diana process oilPW-32” available from Idemitsu Kosan Co., Ltd.), relative to 100 partsby weight of ABSORTOMER was added, and stirred so that the solution washomogenous. Next, the solution was applied on a mold-release-treated PETfilm so that the thickness after drying was 50 μm by using a coater, anddried at 120° C. for 1 hour, to obtain a resin film. A plurality of theobtained resin films having a thickness of 50 μm were layered to obtaina first layer having a thickness of 100 μm.

Further, one of the surfaces of the first layer was irradiated withplasma, and directly after irradiation, a second layer having athickness of 350 μm was pasted on the surface irradiated with plasma.

Composition of Second Layer:

Polyvinyl acetal resin (1) (average polymerization degree: 1700, usingn-butyl aldehyde, acetalization degree 68.5% by mole, content ofhydroxyl group: 30.7% by mole, acetylation degree: 0.8% by mole) 100parts by weight

Triethylene glycol di-2-ethylhexanoate (3GO): 37.5 parts by weight

An amount that is 0.2% by weight in the obtained interlayer film of anultraviolet ray screening agent(2-(2-hydroxy-3-t-butyl-5-methylphenyl)-5-chlorobenzotriazole)

An amount that is 0.2% by weight in the obtained interlayer film of anoxidation inhibitor (2,6-di-t-butyl-p-cresol)

Next, the other of the surfaces of the first layer was irradiated withplasma in the same manner, and a third layer (having the samecomposition as the second layer) having a thickness of 350 μm was pastedon the surface.

An interlayer film (800 μm thick) having a laminate structure of thesecond layer (350 μm thick)/the first layer (100 μm thick)/the thirdlayer (350 μm thick) was prepared.

Laminated glass was obtained in the same manner as that in Example 1except that the obtained interlayer film was used.

Comparative Example 1

The following ingredients were mixed, and kneaded sufficiently with amixing roll to obtain a composition for forming a first layer.

Polyvinyl acetal resin (2) (average polymerization degree: 3050, usingn-butyl aldehyde, acetalization degree 63.7% by mole, content ofhydroxyl group: 24.2% by mole, acetylation degree: 12.1% by mole)

Triethylene glycol di-2-ethylhexanoate (3GO): 60 parts by weight

An amount that is 0.2% by weight in the obtained interlayer film of anultraviolet ray screening agent(2-(2-hydroxy-3-t-butyl-5-methylphenyl)-5-chlorobenzotriazole) An amountthat is 0.2% by weight in the obtained interlayer film of an oxidationinhibitor (2,6-di-t-butyl-p-cresol)

Preparation of Composition for Forming Second Layer and Third Layer:

A composition for forming a second layer and a third layer was obtainedin the same manner in Example 2 except that the blending amount oftriethylene glycol di-2-ethylhexanoate (3GO) was changed to 31.5 partsby weight.

Preparation of Interlayer Film and Laminated Glass:

By coextruding the composition for forming a first layer and acomposition for forming a second layer and a third layer using acoextruder, an interlayer film (800 μm in thickness) having a layeredstructure with a stack of a second layer (350 μm in thickness)/a firstlayer (100 μm in thickness)/a third layer (350 μm in thickness) wasprepared.

Laminated glass was obtained in the same manner as in Example 1 exceptthat the aforementioned composition for forming each layer was used andthe interlayer film was prepared in the method as described above.

Comparative Example 2

An interlayer film and laminated glass were obtained in the same manneras that in Example 2 except that the blending amount of the plasticizerwas set to that shown in the following Table 2.

Comparative Examples 3, 4

An interlayer film and laminated glass were obtained in the same manneras that in Comparative Example 1 except that the blending amount of theplasticizer was set to that shown in the following Table 2.

(Synthesis of (Meth)Acryl Polymers (1) to (7))

A polymerizable composition having the blending composition shown in thefollowing Table 3 was sandwiched between two PET sheets treated to havea mold releaseability on one side (available from NIPPA, having athickness of 50 μm) to form a polymerizable composition layer having athickness of 100 μm. A spacer was arranged around the two PET sheets.The polymerizable composition layer was irradiated with ultraviolet raysat a dose of 3000 mJ/cm² with a high pressure mercury UV lamp to curethe polymerizable composition by reaction. (Meth)acryl polymers (1) to(6) were obtained as mixtures containing a plasticizer (3GO or ATBC).(Meth)acryl polymer (7) was obtained as a cured product not containing aplasticizer.

(Synthesis of Polyvinyl Acetate (1))

A glass polymerization vessel equipped with a reflux condenser, adropping funnel, a thermometer, and a nitrogen inlet was prepared. Thispolymerization vessel was charged with 100 parts by weight of vinylacetate monomer, 1.0 part by weight of 3-methyl-3-buten-1-ol, and 3.8parts by weight of methanol, and heated and stirred, and the interior ofthe polymerization vessel was replaced by nitrogen. Then the innertemperature of the polymerization vessel was controlled to 60° C., and0.02 parts by weight of tert-butylperoxy neodecanate which is apolymerization initiator, 150 parts by weight of vinyl acetate monomer,and 1.5 parts by weight of 3-methyl-3-buten-1-ol were dropped over 4hours, and polymerized for 2 hours after end of the dropping, and thus asolution containing polyvinyl acetate was obtained. The solution wasdried for 3 hours in an oven at 110° C. to obtain polyvinyl acetate (1).

(Synthesis of Polyvinyl Acetate (2))

A glass polymerization vessel equipped with a reflux condenser, adropping funnel, a thermometer, and a nitrogen inlet was prepared. Thispolymerization vessel was charged with 250 parts by weight of vinylacetate monomer and 3.8 parts by weight of methanol, and heated andstirred, and the interior of the polymerization vessel was replaced bynitrogen. Then the inner temperature of the polymerization vessel wascontrolled to 60° C., and 0.06 parts by weight of tert-butylperoxyneodecanate which is a polymerization initiator was dropped over 2.5hours, and polymerized for 2 hours after end of the dropping, and thus asolution containing polyvinyl acetate was obtained. The solution wasdried for 3 hours in an oven at 110° C. to obtain polyvinyl acetate (2).

Example 3 Preparation of First Layer:

A mixture (layer containing a cured product) containing 100 parts byweight of the (meth)acryl polymer (1) obtained in the above, and 15parts by weight of a plasticizer (3GO) was prepared.

Preparation of Fourth Layer and Fifth Layer:

As the fourth layer and the fifth layer, PET film (1) (“TOYOBO esterfilm E5100” available from TOYOBO CO., LTD., 50 μm thick) was prepared.

Preparation of Second Layer and Third Layer:

The following ingredients were mixed, and kneaded sufficiently with amixing roll to obtain a composition for forming a second layer and athird layer.

Polyvinyl acetal resin (3) (average polymerization degree: 1700, usingn-butyl aldehyde, content of hydroxyl group: 31% by mole, butyralizationdegree: 68% by mole, acetylation degree: 1% by mole) 100 parts by weight

Plasticizer (3GO) 35 parts by weight

An amount that is 70 ppm in the obtained interlayer film of Metal salt M(Mg mixture)

An amount that is 0.2% by weight in the obtained interlayer film of anultraviolet ray screening agent (Tinuvin326)

An amount that is 0.2% by weight in the obtained interlayer film of anoxidation inhibitor (BHT)

The composition for forming the second layer and the third layer wasextruded with an extruder to obtain the second layer and the thirdlayer.

Preparation of Interlayer Film:

The first layer was sandwiched between the fourth layer and the fifthlayer to obtain a three-layer laminate. By arranging second layer andthe third layer on the outer sides of the laminate, and laminating witha roll laminator (“GDRB316 A3” available from ACCO BRANDS JAPAN) at 100°C. and a speed setting 3, an interlayer film having a structure of thesecond layer/the fourth layer/the first layer/the fifth layer/the thirdlayer was obtained.

Laminated glass was obtained in the same manner as that in Example 1except that the obtained interlayer film was used.

Examples 4 to 8, Comparative Example 5

An interlayer film and laminated glass were obtained in the same manneras that in Example 3 except that the kinds and the amounts of theingredients were set to that shown in the following Tables 4 and 5. InExamples 4 to 8 and Comparative Example 5, the same kinds of theultraviolet ray screening agent and the oxidation inhibitor as thoseused in Example 3 were blended in the same blending amounts as those inExample 3 (blending amounts in the second layer and in the third layer),and the Mg mixture of the same kind as that in Example 3 was blended inthe same blending amount as that in Example 3 (blending amounts in thesecond layer and the third layer).

Example 9 Preparation of Composition for Forming First Layer:

The following ingredients were mixed, and kneaded sufficiently with amixing roll to obtain a composition for forming a first layer.

Polyvinyl acetate (1) 100 parts by weight

Plasticizer (Bis(2-butoxyethyl) adipate (D931)) 80 parts by weight

An amount that is 0.2% by weight in the obtained interlayer film of anultraviolet ray screening agent (Tinuvin326)

An amount that is 0.2% by weight in the obtained interlayer film of anoxidation inhibitor (BHT)

Preparation of Composition for Forming Second Layer and Third Layer:

The following ingredients were mixed, and kneaded sufficiently with amixing roll to obtain a composition for forming a second layer and athird layer.

Polyvinyl acetal resin (3) (average polymerization degree: 1700, usingn-butyl aldehyde, content of hydroxyl group: 31% by mole, butyralizationdegree: 68% by mole, acetylation degree: 1% by mole) 100 parts by weight

Plasticizer (Bis(2-butoxyethyl) adipate (D931)) 35 parts by weight

An amount that is 70 ppm in the obtained interlayer film of Metal salt M(Mg mixture)

An amount that is 0.2% by weight in the obtained interlayer film of anultraviolet ray screening agent (Tinuvin326)

An amount that is 0.2% by weight in the obtained interlayer film of anoxidation inhibitor (BHT)

Preparation of Interlayer Film and Laminated Glass:

By coextruding the composition for forming a first layer and thecomposition for forming a second layer and a third layer using acoextruder, an interlayer film having a structure of the secondlayer/the first layer/the third layer was obtained.

Laminated glass was obtained in the same manner as that in Example 1except that the obtained interlayer film was used.

Example 10

An interlayer film and laminated glass were obtained in the same manneras that in Example 9 except that the kinds and the amounts of theingredients were set to that shown in the following Table 6. In Example10, the same kinds of the ultraviolet ray screening agent and theoxidation inhibitor as those used in Example 9 were blended in the sameblending amounts as those in Example 9 (blending amounts in the secondlayer and in the third layer), and the Mg mixture of the same kind asthat in Example 9 was blended in the same blending amount as that inExample 9 (blending amounts in the second layer and the third layer).

The details of the ingredients in Table 6 are as follows.

Polyvinyl acetal resin (4) (using n-butyl aldehyde, polymerizationdegree: 1700, content of hydroxyl group: 34.5% by mole, butyralizationdegree: 64.5% by mole, acetylation degree: 1% by mole)

Comparative Example 6

An interlayer film and laminated glass were obtained in the same manneras that in Example 9 except that the kinds and the amounts of theingredients were set to that shown in the following Table 6. InComparative Example 6, the same kinds of the ultraviolet ray screeningagent and the oxidation inhibitor as those used in Example 9 wereblended in the same blending amounts as those in Example 9 (blendingamount in the first layer, blending amounts in the second layer and inthe third layer), and the Mg mixture of the same kind as that in Example9 was blended in the same blending amount as that in Example 9 (blendingamount in the first layer, blending amounts in the second layer and thethird layer).

The details of the ingredients in Table 6 are as follows.

Polyvinyl acetal resin (5) (average polymerization degree: 1700, usingn-butyl aldehyde, content of hydroxyl group: 30% by mole, butyralizationdegree: 69% by mole, acetylation degree: 1% by mole)

Fluorene (additive): 9,9-bis [4-(2-hydroxyethoxy)phenyl]fluorene

(Evaluation) (1) Resonance Frequency and Loss Factor in Secondary Mode

The obtained interlayer film was cut into a size of 25 mm wide and 300mm long. As the first lamination glass member, and the second laminationglass member, two glass plates (clear float glass, 25 mm wide, 300 mmlong and 2 mm thick) were prepared. The interlayer film is sandwichedbetween the two glass plates to obtain a laminate. The laminate was putinto a rubber bag and the interior of the bag was degassed for 20minutes with a degree of vacuum of 2.6 kPa, after which the laminate inthe degassed condition was transferred into an oven, and vacuum-pressedby retention at 90° C. for 30 minutes, and thus the laminate waspreliminarily press-bonded. The preliminarily press-bonded laminate wassubjected to press-bonding for 20 minutes under conditions of 135° C.and a pressure of 1.2 MPa in an autoclave to obtain a sheet of laminatedglass. The obtained laminated glass was stored in an environment at roomtemperature of 23±2° C. and a humidity of 25±5%. After 1 month aftercompletion of the autoclave, the obtained laminated glass was excitedwith a vibration generator for damping test (“Vibrator G21-005D”available from Shinken. Co., Ltd.) in a thermostatic oven at 20° C. Theresultant vibration characteristic was amplified with a mechanicalimpedance measuring device (“XG-81” available from RION Co., Ltd.), andthe vibration spectrum was analyzed with a FFT spectrum analyzer (“FFTanalyzer HP3582A” available from Yokogawa Hewlett Packard) to measure aresonance frequency and the loss factor.

(2) Glass Transition Temperature

The obtained interlayer film was stored for 1 month in an environment atroom temperature of 23±2° C. and a humidity of 25±5%. In the case of aninterlayer film having a single-layered structure, the interlayer filmwas used as is in an environment at room temperature of 23±2° C.directly after storage. In the case of the interlayer film having amultilayer structure, the first layer that was obtained by peeling offthe second layer and the third layer from the interlayer film was pressmolded at 150° C. so that the thickness was 0.35 mm (at 150° C. withoutpressurization for 10 minutes, at 150° C. under pressurization for 10minutes) to prepare a resin film. Then the resin film was measured forviscoelasticity using “ARES-G2” available from TA Instruments. Glasstransition temperature was measured under the condition in which thetemperature was decreased from 100° C. to −50° C. at a temperaturedecreasing rate of 3° C./minute and under the condition of a frequencyof 1 Hz and a strain of 1% by using a parallel plate with a diameter of8 mm as a jig.

(3) Sound Insulating Property

The obtained interlayer film was cut into a size of 500 mm wide and 500mm long. As the first lamination glass member, and the second laminationglass member, two glass plates (clear float glass, 500 mm wide, 500 mmlong and 2 mm thick) were prepared. The interlayer film was sandwichedbetween the two glass plates to obtain a laminate. The laminate was putinto a rubber bag and the interior of the bag was degassed for 20minutes with a degree of vacuum of 2.6 kPa, after which the laminate inthe degassed condition was transferred into an oven, and vacuum-pressedby retention at 90° C. for 30 minutes, and thus the laminate waspreliminarily press-bonded. The preliminarily press-bonded laminate wassubjected to press-bonding for 20 minutes under conditions of 135° C.and a pressure of 1.2 MPa in an autoclave to obtain a sheet of laminatedglass. The obtained laminated glass was stored for 1 month in anenvironment at room temperature 23±2° C. and a humidity of 25±5%.

Sound transmission loss of the obtained laminated glass was measured bythe method in accordance with JIS A 1441-1, the sound insulatingproperty was judged according to the following criteria from sum S ofvalues of sound transmission loss at 2500 Hz, 3150 Hz, 4000 Hz, 5000 Hz,and 6300 Hz from A to near B in FIG. 5.

[Criteria for Judgment in Sound Insulating Property]

◯: S is 210 dB or more

Δ: S is 205 dB or more and less than 210 dB

X: S is less than 205 dB

The details and the results are shown in the following Tables 1 to 6. Inthe following Tables 1, 2, and 4 to 6, the description of ingredients tobe blended other than resins, plasticizers, adhesive strength adjustingagents, and additives was omitted.

TABLE 1 Example 1 Example 2 Interlayer Second Thickness (μm) 350 filmlayer Kind of cured product or resin Polyvinyl acetal resin (1) Blendingamount of cured product or 100 resin (parts by weight) Kind ofplasticizer 3GO Blending amount of plasticizer 37.5 (parts by weight)First Thickness (μm) 800 100 layer Kind of cured product or resinAliphatic Aliphatic polyolefin polyolefin Blending amount of curedproduct or 100 100 resin (parts by weight) Kind of plasticizer Dianaprocess Diana process oil PW-90 oil PW-32 Blending amount of plasticizer40 35 (parts by weight) Kind of adhesive strength adjusting ARHFONUH-2041 — agent Blending amount of adhesive strength 5 — adjusting agent(parts by weight) Third Thickness (μm) 350 layer Kind of cured productor resin Polyvinyl acetal resin (1) Blending amount of cured product or100 resin (parts by weight) Kind of plasticizer 3GO Blending amount ofplasticizer 37.5 (parts by weight) Evaluation Resonance frequency (Hz):X 633 603 Loss factor in secondary mode: Y 0.412 0.376 0.0008X − 0.1420.364 0.340 Judgement of Y > 0.0008X − 0.143 ∘ ∘ Presence or absence ofglass transition Presence Presence temperature of first layer intemperature range of −10° C. to 10° C. Glass transition temperature offirst layer −3.8 −6.7 (° C.) Sound insulating property (sound 41.7 41.5transmission loss at 3150 Hz) (dB) Sound insulating property (sound 45.744.2 transmission loss at 6300 Hz) (dB) Sound insulating property (S) ∘∘

TABLE 2 Comparative Comparative Comparative Comparative Example 1Example 2 Example 3 Example 4 Interlayer Second Thickness (μm) 350 350350 350 film layer Kind of cured product or Polyvinyl acetal Polyvinylacetal Polyvinyl acetal Polyvinyl acetal resin resin (1) resin (1) resin(1) resin (1) Blending amount of cured 100 100 100 100 product or resin(parts by weight) Kind of plasticizer 3GO 3GO 3GO 3GO Blending amount of31.5 37.5 37.5 39.5 plasticizer (parts by weight) First Thickness (μm)100 100 100 100 layer Kind of cured product or Polyvinyl acetalAliphatic Polyvinyl acetal Polyvinyl acetal resin resin (2) polyolefinresin (2) resin (2) Blending amount of cured 100 100 100 100 product orresin (parts by weight) Kind of plasticizer 3GO Diana 3GO 3GO processoil PW-32 Blending amount of 60 50 60 60 plasticizer (parts by weight)Kind of adhesive strength — — — — adjusting agent Blending amount of — —— — adhesive strength adjusting agent (parts by weight) Third Thickness(μm) 350 350 350 350 layer Kind of cured product or Polyvinyl acetalPolyvinyl acetal Polyvinyl acetal Polyvinyl acetal resin resin (1) resin(1) resin (1) resin (1) Blending amount of cured 100 100 100 100 productor resin (parts by weight) Kind of plasticizer 3GO 3GO 3GO 3GO Blendingamount of 31.5 37.5 37.5 39.5 plasticizer (parts by weight) EvaluationResonance frequency (Hz): X 946 540 669 739 Loss factor in secondarymode: Y 0.232 0.352 0.367 0.381 0.0008X − 0.142 0.615 0.290 0.393 0.449Judgement of Y > 0.0008X − 0.143 x ∘ x x Presence or absence of glassPresence Absence Presence Presence transition temperature of first layerin temperature range of −10° C. to 10° C. Glass transition temperatureof 3.5 −14.5 −4.5 −2.3 first layer (° C.) Sound insulating property(sound 38.1 42.3 41.3 41.2 transmission loss at 3150 Hz) (dB) Soundinsulating property (sound 45.5 35.5 40.8 42.1 transmission loss at 6300Hz) (dB) Sound insulating property (S) x x x x

(Meth)acryl (Meth)acryl (Meth)acryl (Meth)acryl (Meth)acryl (Meth)acryl(Meth)acryl polymer (1) polymer (2) polymer (3) polymer (4) polymer (5)polymer (6) polymer (7) Ingredient EA Parts by 40 21 35 weight BzA Partsby 32 33 45 45 45 45 23 weight CTFA Parts by 18 33 33 33 33 weight HPAParts by 28 28 22 22 22 22 weight HEA Parts by 10 weight BA Parts by 32weight IRGACURE Parts by 0.2 0.2 0.2 0.2 0.2 0.2 10 184 weight 3G0 Partsby 15 20 32 weight ATBC Parts by 40 42.5 45 47.5 weight

The details of the components shown in Table 3 used in synthesis of(meth)acryl polymers (1) to (7) are as follows.

EA: ethyl acrylate (available from NIPPON SHOKUBAI CO., LTD.)

BzA: benzyl acrylate (available from OSAKA ORGANIC CHEMICAL INDUSTRYLTD., VISCOAT #160)

BA: butyl acrylate (available from NIPPON SHOKUBAI CO., LTD.)

HEA: 2-hydroxyethyl acrylate (available from OSAKA ORGANIC CHEMICALINDUSTRY LTD.)

CTFA: cyclic trimethylolpropane formal acrylate (available from OSAKAORGANIC CHEMICAL INDUSTRY LTD., VISCOAT #200)

HPA: hydroxypropyl acrylate (available from OSAKA ORGANIC CHEMICALINDUSTRY LTD.)

IRGACURE 184: 2,2-dimethoxy-1,2-diphenylethane-1-one (available fromBASF)

3GO: triethylene glycol di-2-ethylhexanoate

ATBC: acetyl tributyl citrate (available from Taoka Chemical CO., Ltd.)

Example 3 Example 4 Example 5 Example 6 Interlayer Second Thickness (μm)380 380 380 380 film layer Kind of cured product or Polyvinyl acetalPolyvinyl acetal Polyvinyl acetal Polyvinyl acetal resin resin (3) resin(3) resin (3) resin (3) Blending amount of cured 100 100 100 100 productor resin (parts by weight) Kind of plasticizer 3GO 3GO 3GO 3GO Blendingamount of 35 35 35 35 plasticizer (parts by weight) Fourth Thickness(μm) 50 50 50 50 layer Kind PET film (1) PET film (1) PET film (1) PETfilm (1) First Thickness (μm) 100 100 100 100 layer Kind of curedproduct or Meth(acryl) Meth(acryl) Meth(acryl) Meth(acryl) resin polymer(1) polymer (2) polymer (3) polymer (4) Blending amount of cured 100 100100 100 product or resin (parts by weight) Kind of plasticizer 3GO 3GOATBC ATBC Blending amount of 15 20 40 42.5 plasticizer (parts by weight)Kind of adhesive strength — — — — adjusting agent Blending amount of — —— — plasticizer (parts by weight) Fifth Thickness (μm) 50 50 50 50 layerKind PET film (1) PET film (1) PET film (1) PET film (1) Third Thickness(μm) 380 380 380 380 layer Kind of cured product or Polyvinyl acetalPolyvinyl acetal Polyvinyl acetal Polyvinyl acetal resin resin (3) resin(3) resin (3) resin (3) Blending amount of cured 100 100 100 100 productor resin (parts by weight) Kind of plasticizer 3GO 3GO 3GO 3GO Blendingamount of 35 35 35 35 plasticizer (parts by weight) Evaluation Resonancefrequency (Hz): X 723 625 716 676 Loss factor in secondary mode: Y 0.5020.436 0.506 0.487 0.0008X − 0.142 0.436 0.358 0.431 0.399 Judgement ofY > 0.0008X − 0.143 ∘ ∘ ∘ ∘ Presence or absence of glass PresencePresence Presence Presence transition temperature of first layer intemperature range of −10° C. to 10° C. Glass transition temperature of−6.6 −8.4 −5.3 −6.5 first layer (° C.) Sound insulating property (S) ∘ ∘∘ ∘

TABLE 5 Comparative Example 7 Example 8 Example 5 Interlayer SecondThickness (μm) 380 380 380 film layer Kind of cured product or Polyvinylacetal Polyvinyl acetal Polyvinyl acetal resin resin (3) resin (3) resin(3) Blending amount of cured 100 100 100 product or resin (parts byweight) Kind of plasticizer 3GO 3GO 3GO Blending amount of 35 35 35plasticizer (parts by weight) Fourth Thickness (μm) 50 50 50 layer KindPET film (1) PET film (1) PET film (1) First Thickness (μm) 100 100 100layer Kind of cured product or Meth(acryl) Meth(acryl) Meth(acryl) resinpolymer (5) polymer (6) polymer (7) Blending amount of cured 100 100 100product or resin (parts by weight) Kind of plasticizer ATBC ATBC —Blending amount of 45 47.5 — plasticizer (parts by weight) Kind ofadhesive strength — — — adjusting agent Blending amount of adhesive — —— strength adjusting agent (parts by weight) Fifth Thickness (μm) 50 5050 layer Kind PET film (1) PET film (1) PET film (1) Third Thickness(μm) 380 380 380 layer Kind of cured product or Polyvinyl acetalPolyvinyl acetal Polyvinyl acetal resin resin (3) resin (3) resin (3)Blending amount of cured 100 100 100 product or resin (parts by weight)Kind of plasticizer 3GO 3GO 3GO Blending amount of 35 35 35 plasticizer(parts by weight) Evaluation Resonance frequency (Hz): X 649 612 760Loss factor in secondary mode: Y 0.465 0.428 0.412 0.0008 X − 0.1420.377 0.348 0.466 Judgement of Y > 0.0008X − 0.143 ∘ ∘ x Presence orabsence of glass Presence Presence Presence transition temperature offirst layer in temperature range of −10° C. to 10° C. Glass transitiontemperature of −7.7 −8.9 −7.7 first layer (° C.) Sound insulatingproperty (S) ∘ ∘ x

TABLE 6 Comparative Example 9 Example 10 Example 6 Interlayer SecondThickness (μm) 380 380 330 film layer Kind of cured product or Polyvinylacetal Polyvinyl acetal Polyvinyl acetal resin resin (3) resin (4) resin(5) Blending amount of cured 100 100 100 product or resin (parts byweight) Kind of plasticizer D931 D931 3 GO Blending amount of 35 33 36plasticizer (parts by weight) First Thickness (μm) 100 100 150 layerKind of cured product or Vinyl acetate Vinyl acetate Vinyl acetate resin(1) (1) (2) Blending amount of cured 100 100 100 product or resin (partsby weight) Kind of plasticizer D931 D931 3GO Blending amount of 80 70 60plasticizer (parts by weight) Kind of additive — — Fluorene Blendingamount of additive — — 100 (parts by weight) Third Thickness (μm) 380380 330 layer Kind of cured product or Polyvinyl acetal Polyvinyl acetalPolyvinyl acetal resin resin (3) resin (4) resin (5) Blending amount ofcured 100 100 100 product or resin (parts by weight) Kind of plasticizerD931 D931 3GO Blending amount of 35 33 36 plasticizer (parts by weight)Evaluation Resonance frequency (Hz): X 689 643 1010 Loss factor insecondary mode: Y 0.423 0.425 0.100 0.0008X − 0.142 0.409 0.372 0.666Judgement of Y > 0.0008X − 0.143 ∘ ∘ x Presence or absence of glassPresence Presence Absence transition temperature of first layer intemperature range of −10° C. to 10° C. Glass transition temperature of 0−4.5 22 first layer (° C.) Sound insulating property (S) Δ ∘ x

EXPLANATION OF SYMBOLS

-   -   1: First layer    -   1 a: First surface    -   1 b: Second surface    -   2: Second layer    -   2 a: Outer surface    -   3: Third layer    -   3 a: Outer surface    -   11: Interlayer film    -   11A: Interlayer film (first layer)    -   11 a: First surface    -   11 b: Second surface    -   21: First lamination glass member    -   22: Second lamination glass member    -   31: Laminated glass    -   31A: Laminated glass

1. An interlayer film for laminated glass having a one-layer structureor a two or more-layer structure, the interlayer film including a resinlayer containing a thermoplastic resin and a plasticizer, and theinterlayer film having a resonance frequency X of 550 Hz or more and 740Hz or less, a loss factor Y in a secondary mode of 0.35 or more and 0.70or less, and satisfying a formula: Y>0.0008X−0.142 in a measurement ofresonance frequency in a secondary mode in a damping test for laminatedglass according to a central exciting method of laminated glass, whenthe laminated glass is obtained by arranging the interlayer film betweentwo glass plates of 25 mm wide, 300 mm long and 2 mm thick. 2.(canceled)
 3. (canceled)
 4. The interlayer film for laminated glassaccording to claim 1, wherein the thermoplastic resin is a thermoplasticelastomer.
 5. The interlayer film for laminated glass according to claim4, wherein the thermoplastic elastomer is an aliphatic polyolefin. 6.The interlayer film for laminated glass according to claim 5, whereinthe aliphatic polyolefin is a saturated aliphatic polyolefin.
 7. Theinterlayer film for laminated glass according to claim 1, wherein theplasticizer is a plasticizer other than an organic ester plasticizer. 8.The interlayer film for laminated glass according to claim 1, whereinthe plasticizer is paraffin oil.
 9. The interlayer film for laminatedglass according to claim 1, comprising: a first layer; and a secondlayer arranged on a first surface side of the first layer.
 10. Theinterlayer film for laminated glass according to claim 9, wherein whenan overall thickness of the interlayer film for laminated glass is T,the first layer has a thickness of 0.25T or less.
 11. The interlayerfilm for laminated glass according to claim 9, further comprising athird layer arranged on a second surface side opposite to the firstsurface side of the first layer.
 12. The interlayer film for laminatedglass according to claim 11, wherein the second layer contains athermoplastic resin and a plasticizer, and the third layer contains athermoplastic resin and a plasticizer.
 13. The interlayer film forlaminated glass according to claim 1, which is used for obtaininglaminated glass by being arranged between a first glass plate having athickness of 1.8 mm or more and 3 mm or less, and a second glass plate.14. The interlayer film for laminated glass according to claim 1,wherein the interlayer film is used for obtaining laminated glass bybeing arranged between a first glass plate and a second glass plate, anda total of a thickness of the first glass plate and a thickness of thesecond glass plate is 3.6 mm or more and 6 mm or less.
 15. A laminatedglass comprising: a first lamination glass member; a second laminationglass member; and the interlayer film for laminated glass according toclaim 1, the interlayer film for laminated glass being arranged betweenthe first lamination glass member and the second lamination glassmember.
 16. The interlayer film for laminated glass according to claim1, wherein the thermoplastic resin is polystyrene, an ethylene-vinylacetate copolymer resin, an ethylene-acrylic acid copolymer resin, apolyurethane resin, a polyvinyl alcohol resin, a polyvinyl acetateresin, a polyester resin or a (meth)acryl polymer.
 17. The interlayerfilm for laminated glass according to claim 1, wherein the thermoplasticresin is polystyrene, an ethylene-vinyl acetate copolymer resin, anethylene-acrylic acid copolymer resin, a polyurethane resin, a polyvinylalcohol resin, a polyvinyl acetate resin, or a polyester resin.
 18. Theinterlayer film for laminated glass according to claim 1, wherein theplasticizer of the resin layer is in a content of 10 parts by weight ormore and 60 parts by weight or less relative to 100 parts by weight ofthe thermoplastic resin in the resin layer.
 19. The interlayer film forlaminated glass according to claim 1, further comprising a metal saltselected from the group consisting of an alkali metal salt, an alkaliearth metal salt, and a magnesium salt.
 20. The interlayer film forlaminated glass according to claim 1, further comprising an oxidationinhibitor selected from the group consisting of a phenol-based oxidationinhibitor, a sulfur-based oxidation inhibitor, and a phosphorus-basedoxidation inhibitor.